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Tamper-proof EPA engine programming
Vehicle Speed Limiter (VSL) and Engine Idle Shutdown Timer (EIST) are Emission Controls that may be noted on the door label. The default VSL speed is 64 MPH and EIST requires 5 minute idle shutdown. The expiration distance for these parameters is between for 300,000 - 1,259,000 miles and CANNOT BE RESET during that period. The expiration is not noted anywhere on the vehicle. You must call Parts and get this number, and use an engine tool to remove the value when applicable, if desired.
Propane chassis
Most propane bottles have a RH side pump and thus requires a RH side PTO with a jackshaft to connect the two. 
Omitting mud flaps
Some OEs offer this option and it saves money when fleets or body builders will be installing their own branded flaps. Ask the question.
Previous chassis
Listing a previous chassis can be advantageous, if the chassis is the same model or was built within the same emission level. If this is not the case it is best to find a way to communicate the features about the previous chassis that you would like carried forward.
Asphalt dump brake chamber clearance
Choose to invert the brake cans to rotate them forward of the rear tires and away from the asphalt roller. 22.5 tires get a smaller brake 24/30 vs. the 24.5 which gets a 30/30. Some OEs use 30/30 exclusively, so with the smaller tires, their brakes will protrude past the tires and interfere.  If you add two pushers, then regardless which tires are on the drive axles, the spring brake cans will change to 36 inch (30/36) and you’ll have an issue.  The only correct way to resolve is to change to disc brakes or use a suspension that puts the cans on the front side of the axle.
6S/6M antilock brakes
Some OEs are standard with 4S/4M braking system (Sensors/Modulators). Tractor specs should always use six sensors since FMVSS136 came into effect in 2019. Come to training and we will explain how these systems work, and if it makes sense to use the 6S/6M.
PTO programming
If you need to control the engine RPM in PTO mode, its best to orders a PTO switch from the factory.  Without it, your shop or customer could have to add a wire from the PTO or PTO switch to the engine ECM to let the engine know to go to PTO RPM. One can never tell when a chassis will require a PTO in its second or third life. 
Artic Fox fuel heaters
These products use engine coolant to warm fuel in the tanks.  If your customer is gelling before warm coolant is available, they won’t do much good. They have a thermostat, thus will automatically shut off in warm weather. 
15 x 8.625 Bendix brakes
These brakes have a maximum capacity of 20K per axle and are not available for tractors. Typically used on car haulers with 19.5” wheels.  Maximum tire SLR (Static Loaded Radius) is 18.5”, so small tires are required. 
Brake sizes
One would think that the 16.5X8.6 brake would come with a larger GAWR than the 16.5X7, but they don’t always. Here are some common cpacities. 16.5 x 8.625 brakes have a maximum GAWR = 23K per axle for Full Truck / 26K for Tractors: 16.5 x 7 brakes have a maximum GAWR = 29K per axle for Full Truck / 26K for Tractors. 
Skully System
This is commonly something fuel tankers require.  It requires power to the 7 wire on the 7 way (J560) all the time (key does not shut this circuit off).  The Skully monitors the fuel level in the tank to keep from overfilling.  Select an option from the factory to keep the 7 wite on J560 plug hot all the time with ABS. 
Rear brake camshaft reinforcement and gusseted cam brackets
These options support the cam shaft bracket from vibration and failure. They are required with the following: Vocational / refuse applications, Export service, Most tractors, * Large brakes (16.5x6 or 7 on steer; 18x7 on drive), GAWR > 23k on Drive Axle, Mid or Wide track axles, 36 inch park brake chambers
The standard 1650 torque clutch is a 4 paddle
To get a 6 paddle (recommended for frequent start/stopping and vocational applications), select a larger torque capacity cluch (1850).  Yes there is more pedal effort with this clutch, which has little to do with durability, but the 6 paddle will guarantee longer life because of the increased surface area.
LQ-5 valve
This valve is used in asociation with a pusher or tag.  It reduces air pressure to the service brakes, thus helps with flat spotting tires.   This valve is not available through most OEs.  If your customer is interested in reducing flat spotted ties, you might ask your shop or body builder if they would be interested in adding.  This valve drops the application air pressure (approximately) in half.  For example, with a 40 psi foot pedal application, the lift axle brakes get 20 psi.  Full application pressure is passed though at full pressure, so they will lockup regardless. This valve would only be required on axles in the 8K-13.5K range.  20K axles usually are loaded to 20K. 
Flat spotting lift axle tires
Most lift axles are in the 8K-13.5K range are the lightest loaded axle on the vehicle, so when brake pressure increases, the first tires to smoke (lock up) are the lifts. With this in mind there is no actual benefit to disc brakes on lift axles. ABS does not sense these axles.
Steering gears with pushers 
Steering gears don’t have a creep rating so if you spec a 20K pusher, I’d highly recommend twin TAS85 which are rated in the 30K+ range.  The other twin gears are in the 20K range and could have limited performance off road, axle/s up.  With a raised 20K lift, it will load the steer in the 27-28K lbs. range. With 20K gears, the driver steering effort increases dramatically. 
Tractors and aftermarket lift axles
In todays world we need to be installing lift axles on Tractors at the factory. This is due to the FMVSS136 requirement for Electronic Stability Control (ESC) on these vehicles. The program ECM must be programmed to include all axles. I have never heard of an ECM being reprogrammed after the factory to include aftermarket lift axles.
Heavy Haul
The first question should always be "how heavy?". In most applications <140K isnt considered heavy and does not carry a lot of unique considerations. Again, it depends on the application.
5th wheel kingpin rating
With respect to horizontal rating, the FW2570 has a maximum drawbar pull capacity of 150,000 lbs.  This is the amount of horizontal force the 5th wheel can withstand; not the maximum allowable trailer weight.  To determine if the trailer weight of 250,000 pounds is acceptable, we can look at a couple practical examples to understand how much force the 5th wheel will encounter. Example 1: The peak horizontal force the 5th wheel will see is limited by how much traction the tractor has at the ground.  The maximum force is exerted just before the drive tires spin under power.  So, if we calculate the maximum tractive force of the tractor we’ll know how much force is transmitted through the 5th wheel.  The formula is simple:  Multiply the vertical load on the drive axles by the coefficient of friction of the road surface.  Let’s assume 78,000 pounds on drive axles and a worst-case coefficient of friction of 1.0.  Therefore the maximum horizontal force is 78,000lbs x 1.00 = 78,000 lbs.  This is well within the capacity of the 5th wheel. Example 2: Another example is to calculate the Total Grade Resistance of the trailer, or in other words the amount of force required to pull a trailer up a given grade on a given road surface.  The formula for total grade resistance or TGR = (Gross Weight) x (Grade% + Rolling Resistance%) / 100.  In this example, we’ll use 250,000 pounds for the gross trailer weight, 8% for the grade and 16% for the rolling resistance which is representative of rutted soft ground.  So the TGR = 250,000 x (8% + 16%)/100 = 60,000 lbs.  This is also well within the drawbar pull rating of the FW2570. 
8-bolt transmission PTO’s
Many truck models today offer hydraulic clutch assist of some sort. The solenoid to support this is located in the transmission area and can interfere with the 8-bolt PTO mounting. The actuator can be rotated after the chassis is built, however the bleeder valve moves to the bottom, making it useless.   
6-bolt transmission PTO’s
All PTO’s can encounter an issue with internal transmission coolers which prevent most 6 bolt PTO installations, so with multiple PTO’s, look specifically at the transmission explanation for which cooler is called out.  Basically, do your homework.
Transfercase and splitshaft coolers
Any application (like oil fields) where the chassis will be in the mud, use water to oil type cooler.  Exceptions: Eaton AT1202 is not available with oil cooler. TTC/Spicer has its own oil cooler option that is required 4240320 as well as a signed warranty waiver (Waiver comes through Engineering).
Cooling loop
Used for some tankers to keep product from freezing. 
Fabco will need the following so vendor approval which is required on all Fabco’s can be submitted: •HP rating of the pump •Speed of the pump •Length of the operating cycle
Coolant ports for engines
Some port count options are DEF tank, Cab, Sleeper heater, Transmission and/or, Auxiliary Transmission cooler, Split shaft/Transfercase cooler, APU connections, Artic Fox, etc.  Given that, you could easily max out. 
X-30 steer axle drums
Are not commonly used since the Reduced Stopping Distance laws went into effect.  This light weight drum can chatter with the wider brakes, glazing which can cause a squeal.  In a weight sensitive application, use Castlites on the steer and X-30’s on the drive, or switch to air disc brakes.
Allison 1000/2000 PTO operation
The 1000/2000 PTO operates like a manual transmission. The only way to put the PTO in gear is to stop the truck. If the torque converter is in lockup (higher gears), the speed of the PTO drive gear is equal to engine speed (Lockup Mode). If you need a LIVE PTO, this is not your transmission. If in converter mode (lower gears, neutral, reverse), result is variable speed and torque/RPM is always lower than engine speed. See attached. NOTE: With the vehicle stopped and the engine at idle, PTO output speed is dependent upon the trans gear selection: • If the transmission is in a DRIVE gear or REVERSE, PTO output speed is zero. • If the transmission is in NEUTRAL or PARK, the PTO output will rotate slowly.
Allison 3000/4000 PTO operation
The 3000/4000 series transmission PTO’s are driven off the pump side of the converter, so when the engine cranks, the PTO gear turns, which allows for a hot shot PTO. The 1000/2000 operate completely different than the 3000/4000 in PTO mode. Don’t see this as a price shortcut, operation is a HUGE consideration.
Allison PTO
The 1000/2000 series transmissions use a 6-bolt PTO. Larger "World" (3000/4000 series) transmissions uses a 10-bolt.
RSD (Reduced Stopping Distance)
Prior to 2011, 3 axle tractors were required to stop within 350 feet. Reduced Stopping Distance Phase 1 lowered that distance to 250 feet in 2013 for most tractors. Phase 2 in 2013 took into account more configurations and set the distance for these ar 310 feet. This is a requirement by the government for today’s TRACTORS ONLY.
Sleeper Sizes
A 44” sleeper is actually 38.3” when measured from BOC (5.7” difference). 72” sleeper is 64.6” (7.4” difference). 80” sleeper is 72.3”. (7.7”) Some OEs use 10” across the board on all intergrated sleepers, IE: 38” (28”), 52” (42”) and 76” (66”). The only sleeper which doesn’t follow this convention typically is a modular style, whihc is not very common these days. Modular (detached) sleepers are usually equal the outsid measurement of the box, plus he gap between it and BOC.
B vs. C transmission gearing
Some “experts” are pushing B gearing for better fuel economy vs. the C ratio. Look closely at the gear splits. If the truck is starting/stopping a lot, then the tighter split of a B ratio throughout the range could help, but with a sacrifice of significant 1st gear startability compared with the C ratio. If it’s a line haul and most of the time spent in the top 3 gears, then it doesn’t really matter. Both of these 10-spd transmissions have approximately a 400 RPM split in the top gears.
Custom chassis layout
If the OE offers any form of clear frame specification or layout customization it is in the customers best interest to pursue it. Moving components in the aftermarket is expensive and takes time. Plus its always best not to rework airlines and wiring unless absolutely necessary.
Optional longer studs
Steel wheels are thinner material than aluminum wheels, so if you order steel from the OE the studs will not be long enough to change out to aluminum wheels. Changing studs in the shop will cost in the $600 per axle range. Some Oes offer a lowcost option to build the truck with the longer studs and steel wheel for increased flexibility. This could be a low cost solution.
Thrushaft PTO’s. 
Rule of thumb, you mount this on many transmissions (Including Ultrashift Plus), except those which have a back gear box, such as a 13-spd, 18-spd, and 9A convertible. If you want to know for sure, go to Eaton’s PTO information guide. Not to be used on an Allison. ALSO: The PTO’s themselves can be pretty expensive, so price out the whole package. ($5K for a 541 series).
2-spd fan hub vs. On/Off style
A 2-spd fan hub runs at half speed all the time, bumping up to full speed only as needed. There was an unscientific experiment on two chassis, one with on/off and the other with the 2-spd. The trucks idled for 6 hours at 15 degree ambient. The coolant temp was 20 degrees different cooler on the chassis with the 2-spd cooler, making cab heater not as efficient. Before you automatically opt for the 2-spd hub, you might give thought to this cold weather condition. If you have a sleeper chassis without an APU, you might consider the single speed.
2-spd fan hub, converted to On/Off
If you purchased a 2-spd fan hub and are encountering heater issues there is a document from Horton on how to modify it to an ON/OFF function. Will help to resolve a number of over cooling issues for winter operation.
Driving a truck without a CDL
Federal Regulations: If you are caught driving a commercial motor vehicle without a CDL, Federal guidelines indicate that you could be fined up to $2,500 or with aggravated (multi-violations), the penalty could go as high as $5,000. An employer who is convicted of a violation of § 383.37(d) shall be subject to a civil penalty of not less than $2,750 nor more than $25,000. The driver could lose 2 points off their license as well. State Regulations: Specifically, in California, and according to the 2014 Traffic Infraction Bail and Penalty Schedules, the total state fine is $238.00. These violations carry no DMV points against a driver’s license. Section 12500 (d) CVC states this is an offense that is eligible for correction, commonly known as a fix-it ticket. This will be noted on the citation and if corrected the bail is $25.00. However, 30 counties in the state may exceed the total bail amount
Dana axle shaft size
The DSP40, DSP41, and DSH44 all have a 1.88” shaft. The DSH40 has a 1.81” diameter. So if you order the DSH44 on a 46K suspension, the axle shaft is about the same size and strength as 40K. The D40-170, D46-170, DT463, T69-170 have a 2.06” diameter shaft. The D46-590, D52-190, T78-190, D60-190, D52-190, D52-590, D60-590, DT521, TDT583, and D70-590 have a 2.25” diameter shaft. The larger the shaft, the more robust. Today, the axle shaft is the weak link in the drivetrain and is the easiest to fix when a drivetrain failure occurs.
Dana housing size
The DSP40 housing is 9.5mm thick. DSP41, DSH40 and D40-170 are 11mm. D46-170, DSH44 are 12.5mm. DT463 is 14mm. T69-170, T78-190, D60-190, D52-190, D52-590, D60-590, DT521, TDT583, and D46-590 are all 16mm. D70-590 is 22mm.
The new AdvanTEK40 axle is designed to be used with the new Ultrashift “S” ratio Fuller Transmissions. Notice the ratios at 2.26, 2.39, 2.53, 2.64, and 2.79. These are meant to be used with the .80 (S) ratio transmission overdrive gear. The idea behind this combination is to reduce the 400 RPM split on a standard 10B or 10C transmission to about 200, much like a 13-spd, to keep the engine closer to the sweet spot. Advantek40 Axles and Advantage trans: These ratios lower the engine RPM drastically, much like downspeeding. Remember, all these hardware changes are designed to drive the engine RPM lower. The thing about taking engine RPM down to astonishingly low levels is that oil pumps turn slower, crankshafts aren’t churning as much, water pumps turn slower, accessory equipment like power steering pumps, compressors, engine fan and alternators also turn slower. This means less parasitic losses and hopefully less fuel used. The combustion process may or may not be optimized at those RPM’s but the reduction in parasitic losses more than offsets any differences in Brake Specified Fuel Consumption. Use the Advantage Automated Transmission. It’s a combination of components that make for the best dynamic fuel economy, not just one. Now see below the difference between the S and C gear ratios for the Advantage trans. The Advantage S-ratio (0.8 OD) is only available as an automated transmission. The gear steps are not equally spaced. There is one short step at the top, and one in the midrange. It will not be offered as a manual transmission The automation will do the shifting, and make good use of engine torque at lower engine speeds. It will not be uncommon to see the engine lugged down to 1000 RPM on a regular basis. The time this configuration will run “one-gear down” will increase. In this case, this is not a bad thing as this gear is direct. It will result in a good engine speed even when the truck is at sub-cruising speeds
Radiator winter front considerations
Covers for the front of the radiator to keep the engine warm, I’ve been against their use for years, ever since the advent of charge air coolers. Today, and given last winter’s nasty cold and some of the unscientific testing, I’ve changed my mind. However I would caution customers about using these any more than necessary, and I would prefer the driver only use them when idling (but that’s not realistic). When the engine is pulling hard, charge air temperatures are a few hundred degrees, but air flow over the cooler is restricted to a small area, making for a large delta T. The cooler is aluminum and this temperature difference is significant. Certainly charge air cooler life can shorten with the winter front, but there are always tradeoffs.
Additional frame holes drilled by rail manufacturer
Some OEs offer this option and it saves time at body builder. Make certain you understand how engineering wants the measurements conveyed, and you could put something as complex as an entire body on without the need to drill a single hole after the vehicle leaves the factory.
The DSP40(P) and 41(P) rear axles are proprietary
These were developed exclusively for PACCAR. The DSP41 is the same as the 40, except for the heavy wall housing. Compared to the DS404/405(P) the DSP axles have: • High-capacity bearings for the half-shafts, input and output shafts, and pinion for longer life with heavier loads, higher torque • Strong hypoid gearing with premium processing for increased durability • A thrust bolt for the ring gear to minimize damage from shock loads • Premium wheel differential for high shock resistance • An upgraded head assembly joint to provide better sealing between the carrier assemble and the axle housing The next step up, the DSH40/41(P) adds a stronger interaxle differential.
The Advantage or FR Series C ratio (.73 OD)
Available as a manual transmission only. Use of this transmission in a downsped configuration will require drivers to make good use of the engine torque at lower engine speeds. They will need to use the sub-1100 RPM range to minimize shift frequency. Driver education is key. They are lighter and have lower losses because of their near dry-sump operation. There’s less oil churning and there’s no lube pump to turn, plus they save weight. More torque input gets to the output which equals a bit better efficiency.
Greaseable front spring pins
These are recommend for vocational applications. Most highway fleets are looking for less maintenance, not more, so the Elastomeric (rubber) pins are just fine. If you convert a customer from rubber (no maintenance) to these make certain they know this is now a manintenance item. Without grease they will freeze up.
Aluminum top plate weight savings
This option weighs 155 lbs, and looks REALLY LIGHT vs. the FW17 (190 lbs.), FW31 (249 lbs.) and FW33 (249 lbs.) Holland plates, so this option saves between 35 to 94 lbs. Customer needs to decide if the weight savings justifies the price. All have a drawbar pull of 150K.
No-spin DT Dana axles
The Eaton No-spin (Detroit type locker, no sw in the dash) is available on both the forward and rear drive Dana axles. This is the only traction option available for the tandem two speed, DT463P, DT521P. Dana can assemble with this option, but would take an OAR to see if we’ll install out of the factory. It’s not a published option. The No-Spin can also be purchased in the aftermarket and installed by the dealer or end user. Regardless, the axle shafts are not a warrantable item. In addition, Dana may not cover any warranty as the drive axle has been modified, so check with your Dana rep for details.
ILS 5th wheel
When specifying sliding 5th wheels please keep in mind that Holland is changing to the ILS assembly as standard in all cases other than those whose purpose does not align with the design. The non-ILS versions can only be secured in the following instances: 1. 60" and 72" sliders 2. 13.2" Fifth Wheel Height 3. Some suspensions greater than 40,000 lbs. 4. Kompensator 5. No-Tilt Convertible
Movable fixed 5th wheels
Typically a fixed fifth wheel with additional drilling so that the customer can manually reposition the wheel as needed. Most common reason to do this is to save weight. If you spec a moveable fixed wheel (regardless of plate), it requires outboard angles which adds another 64 lbs. to all plates, so take the overall weight savings into account before you blindly go down this path.
Wide track in place of standard track steer axle
Contrary to the description, this option has very little effect on a setback axle, so save the money. If a customer insists on the absolute best turn, it won’t hurt. A single steering gear chassis will ALWAYS turn sharper to the left (smaller turning radius) than to the right. If you need to know a value for a municipal bid, contact Sales Engineering. The steering gears do play a small factor in turning, but it’s ever so slight and not worth mentioning.
Wide base single tires (445/50R22.5 and 84160 Alcoa 2” offset wheel)
With aluminum hubs the maximum rear GAWR is 38K regardless of tandem axle rating. Using this combination on a 46K axle, carries the same 38K because the hub is affected, not the axle. You could change from aluminum to iron hubs (rated at 40K) if that would help on either axle. If you need a 44K GAWR, then use iron hubs with a 46K axle and 455/55R22.5 Michelin XDN2 tires (125 psi) on 84161 Alcoa 1.13” offset wheels.
Wheel cut on standard track steer axle
The wheels can greatly affect steering, the small inset will move the wheels outboard. For example, on a 20K front, you’ll get much better turning with the 3.88 offset wheel vs. the 5.81offset.
Auxiliary Power Units supply power for sleeper and cab functions when parked, in lieu of idling the vehicle engine. Work with the body builder, shop, or customer to determine how much space is required. APU space claim on the rail varies between 18” – 30”.
Change order fees
Most OEs charge a fee for changes submitted after the order is received at the Division Office. Limit this by working with the customer and reading the order prior to submittal.
26K and 33K ratings for medium duty
See attached document that explains the Div. position on Medium Duty chassis rated at 26K for CDL and 33K for F.E.T.
Failed batteries on new trucks
Batteries installed on the line are above 80% charged.Their are any number of draining events that occur between build and sale.Idling the truck for a few minutes does nothing to refresh this. Considered Solar chargers. We’ve had a number of reports that they work very well. Anytime you let a lead acid battery drop to 0 charge, they cannot be brought back to life.
Dana/Eaton relationship
In 1998, Dana and Eaton did a mutual component swap. Dana bought the Eaton Commercial Vehicle steer, drive and brake div. Eaton obtained the clutch division. Dana also agreed to not produce the Commercial Vehicle transmissions. Therefore, Eaton Axles and Brake division was dissolved and the products were merged with the Dana Drive Axle and Brake business. Later, the Dana brake business was merged with the Bendix and they created the Bendix Spicer Foundation Brake division of Bendix. Part of this agreement between Dana and Eaton, was field sales and service for both companies would remain under the Eaton Road Ranger organization. This was a 10 year agreement and was renewed annually until 2012. Then Dana decided to discontinue this agreement. Dana created its own sales and field support team. Currently, Dana and Eaton are completely separate companies. There are no ties between the two.
Daytime running lights
Many DOT weigh stations require headlights off when crossing the scale. Make sure you ask your customer if this is required. If so, specify an over-ride switch for day time running lights. This code was generated for a tanker fleet which required this option.
Tire Pressure Monitoring System
One of many options designed to increase tire life and improve fuel efficiency. This may well be once of the more complicated solutions.
Heavy hauls
If you are specing a heavy haul with an auxiliary transmission pulling approximately 190K+, your sales tool might not provide a recommended ratio. Eaton scrutinizes the startability percentage, so if you’d like to know what gear ratio, contact Engineering, or let me know and I’ll run the numbers for you. Rule of thumb would be an absolute minimum of 16% Startability. I use approximately 20% for on/off road heavies. If using an Allison, most sales tools dont take startability into account due to the torque converter, use the local iSCANN. Also spec the SPL250HD-driveline on these heavies, it’s more robust than the 1810.
Asphalt dump brake chamber clearance
If you are hauling asphalt and using a suspension with brake chambers on the front of axle, don’t worry about this option regardless of tire size. Hendrickson, Neway, and Chalmers always position the rear-rear axle brake chambers on the rear side of the housing, some OE suspensions move then to the front side.
Paint chips
The plants do not spray samples, I refer people to Axalta and/or to their local body shop or DuPont store samples. I’m not sure how long it takes to get a sample from Axalta, I usually tell people 14 working days. Axalta, phone number 855-729-2582. Typically its quicker to have a local body shop do this. This is the only fail-safe way to ensure paint color preference.
Fuel systems
Fuel lines must be within 6” in length of each other, regardless of tank position on the frame. The lines must be routed identical, either over or under the frame. The key to this system performing correctly is balance. The splitter valve is NOT the problem if a customer has one tank that overfills, it usually tied to some debris in the tank.
Engine overspeed shutdown
In a fuel rich environment the intake can suck in fumes and overspeed the engine. Shutdowns, a guilatene style pipe block, were designed for Natural gas fields. Some tanker specs require, but if you’re building an off highway oil field chassis, this should be a requirement. It’s all about fuel vapor entering the air take system allowing the engine to run away.
Single vs. two front tow pins
On some models the two pin design is more robust than using a single center-mounted pin. This is only true when both pins are used in tandem. The correct use is to run a cable or br through both and pull from the cable.
Aftermarket ACK124 valve
If you are specing Heavy Hauls with a 20K lift axle, you might want this valve. It is manufactured by Watson Chalin and is designed to equalize the ground loads (not air pressure) between the lift and drive axles within 10%, which is what some states require. You might get an acceptability of the ACK124 valve in writing, per California, after all, they do not formally recognize lift axles. They can be approved depending on port of entry and inspector. I understand some ports in California, Missouri and Oklahoma are writing tickets if you don’t have one ($1400) so more could be on the way. The factories do not install them on the line.
Progressive engine protection system
Shutdown does exactly that after the engine has warned and derated. Derate, will reduce torque with any sensor issue, and helps protect the engine. If you select Warning, that’s exactly what the engine does, it warns the driver of a pending issue, but does nothing to protect the engine as far as derate or shutdown. If a driver takes no action, then eventually they can destroy an expensive engine ($40K-50K). Give this decision some thought and definitely discuss with your customer. Shutdown setting starts with a warning, if ignored goes to derate, then later shuts down the engine.
Aerodynamic changes
As of 2015 vehicles have to be labeled and reported in accordance with how they are put into service, so if you receive a vehicle and then add a roof fairing, after the fact, then you have taken the vehicle out of compliance. This is the guidance the OEs have been given by the EPA. Changes put the liability completely on the modifying dealer. It applies to the first 435,000 miles of the vehicles life, aslo known as First Useful Life of Vehicle (FULV).
Tandem Meritor rear axles
When using the Mid or DUALtrac axles, make sure you spec the 0” wheel offset wide base 14” wheel. If you spec the more popular 2” offset, the tires will be over width. Dana DSP41’s and standard track Meritors use the 2” offset wheels to kick the tires out close to 102” wide. Ideally, the 0” offset wheel is much better for bearing life than the 2” offset.
Super 18s
These configurations are built for Federal Highway, 7 axles = 80K gross. More states than not are regulated at 40’ overall length. Don’t hang a fixed external tow pin, DOT will measure that extra 4-5” in length. Only used removable tow pins. Loading for this configuration will be: 20K steer, 4.66K each of the lift axles, 34K on the drives, and 12K on the stinger. The combination results in a 36’ overall bridge.
Allison Fuel Sense
See attached for an explanation of Allison’s fuel system.
Dana rear axle oil pumps
The pump is located in the forward drive axle and only operates when there is differential speed between the forward and rear tandems. Otherwise when both axles rotate at the same speed the pump is along for the ride and not working, resulting no loss in efficiency. Older models like D462’s and D402’s had power divider gear driven pumps that run all the time thus robbing horsepower.
Full truck and tractor connections
Order a diversion valve any time you will be using both Hosetenna/pogo A&E and EOF A&E frequently. When you do not get the diversion valve, the customer has to manually switch the air and electric lines by hand.
GCW 140K
If you’re customer is truly grossing 140K without a pusher, ask if they would accept 40K axles. These axles are capable at these weights. Many 140K heavy hauls I see had either a DT463, D46 or D52, so either your over specing, customer had a bad experience, or customer is pulling heavier. Allison blanket approval guidelines or specific models may also artifically cap the GCW and not permit you to tell engineering the actual weight. Look at the Dana Application sheet for a D40-170, it’s good for line haul up to 160K, Operation 2 (8%) grade up to 4.10 gearing. Most 140K chassis only need a 13.5K lift or no lift at all, so creep wont be an issue. With 46K axles Engineering reviews the frame strength with axles loaded to capacity Therefore, you may be required to add an insert and use a more expensive rear suspension.
Fuel tank anti-siphon device
These options come highly recommend. It not only prevents siphoning, it also helps keep contamination out of the tank. Anytime you hear of a customer with an overfilling tank, 99% of the time, it’s due to something in the tank. Contamination occurs accidently and on purpose.
Noisy clutch at idle
There is a VCT, Vibration Control Technology, clutch available that can resolve, but it will take an special process if you’re interested in installing at the factory. Sometimes bumping the idle RPM UP helps as well.
DT hubs
If you are working with a heavy haul and they don’t want eith a 2-speed rear axle or auxiliary transmission, you might consider a DT hub. These are NOT factory installed or endorsed, however it’s another concept for gearing reduction. It’s a 3 to 1 reduction at the hub and uses an air shift to revert back to 1 to 1. In essence, take the axle ratio X 3 to get the effective result. A 4.11 X 3 would equal 12.33 ratio. AT1202 w/4.11 would equal 8.38. APO1750-4C w/4.11 would equal 9.74. Back to the DT reduction mode, the speedometer indicates the truck is doing 90MPH, however the truck is only traveling 30MPH, plus the odometer is racking up miles 3 times as fast. Driveline speed should also be taken into account which could cause vibration issues. The hubs would have to be removed to replace brakes. You also won’t be able to increase the factory DTPO GCW rating.
Fuel:DEF fill ratio
When Diesel Emission Fluid (DEF) was first introduced in N.A. heavy duty trucking, the EPA required a 2:1 fill ratio. This means 2 fuel fills to one DEF tank fill. The premise behind this was the limited availablity of DEF at launch. Today DEF is everywhere and the EPA does permit a 1:1 ratio in some instances. This helps with frame component packaging. It is up to the OE to gain compliance for this as an offering.
A Rear Engine PTO (REPTO) requires approximately 37” clear space BOC for hydraulic pump mounting. REPTO also moves the ESP sensors, when specified, out of the way of the driveshaft. Also request an option to add a REPTO access door in the floor for servicing.
Dash sw/light off-highway for ABS
When you order the Automatic Traction Control option tied to the ABS system (aka “ATC”), an optional switch can be specified on the dash labeled “TC” in a cross-section depiction of a tire. What does this switch do? Press and release the switch, and ATC goes into “mud-and-snow” mode, which allows a little more wheel spin than otherwise, and keeps from backing off the throttle a little longer. This helps prevent the truck from bogging down in mud or snow conditions, which could lead to becoming completely stuck. A light advises the driver that this feature is engaged. The system stays in this mode until either a) the switch is pressed again, b) the truck reaches 25 mph, or c) the key is turned off. Perception is this sw turns off the ABS/ATC, but that is not true.
Air ride suspension on Federal Bridge mixers
Previously this wasn’t even thought about, but today, given the air ride and stability improvements, it might be considered. Some OE’s are using the 52K Primaax. Neway is interested in joining this business. Let me know if you need a Neway contact.
8k lift axles
These axles frequently come standard with the outer ends, tires and wheels.
Meritor rear axle oil pumps
Meritor Drive Axle Pump (P) operates different than Dana. They pump continuously if the axles are going forward or reverse without waiting until a differentiation event occurs. This gives constant lubrication protection to input shaft assembly. The Meritor Drive Axle pump is an option on the MT14X and RT160 series carriers.
Auxiliary transmission
I have found that Eaton will approve the AT1202 up to 240K in low range. I’d recommend contacting Engineering to verify in your application because some part of the spec might preclude using this box. However it was approved using 12R24.5 tires with 18-spd or 4500RDS transmission and 550HP/1850 torque engines.
BOS/C jump start terminals
BOS/C jump start terminals are a good option when pulling a refer, flat bed, heavy haul, basically anything involving powered equipment. That way the equipment or the refer can be jump started, or in the case of the refer, also run a couple wires if the alternator fails.
Hopefully you are not aligning new chassis. The factory uses a very reproducible laser alignment which is second to none. Chassis are assembled upside down and suspensions are mounted in rubber/silicone bushings. It takes time for chassis to seek the sweet spot but only after the chassis has been loaded, so it’s recommended the customer put approximately 10K on the chassis before taking any action. Aligning a new chassis gets down to who’s equipment is the best, and the factory has the best. The factory should know, they have tried them all. Now if there is tire wear, or the chassis is pulling, then you should have it looked at as soon as possible. The key to any good alignment is how often the equipment is calibrated, so ask the aligner before committing Look at TMC (Truck Maintenance Council) recommendations on alignment. They fully understand what’s required.
Longer wheel studs
If your customer thinks at some point, they will change from wide base to dual aluminum wheels, you might spec the longer wheel studs for rear axles. It will cost approximately $600/axle to change those studs after the fact. With long stud option, the customers will always get the longest stud offered with the hub configuration ordered and will be able to mount the thickest single wheel or dual wheel pair with either Lt Wt (X30) or standard cast drums. See how the studs are regulated today: short length studs - dual steel or super single steel wheels with any drums - super single alum wheels with X-30 drums medium length studs - dual alum wheels with X-30 drums (Customer won’t be able to change to cast drums later w/o changing studs) - steel inner & alum outer wheels with any drums - super single alum wheels with cast drums long length studs - dual alum wheels with cast drums - request for longer studs - Alcoa severe service wheels
Rear axles and GCW
Go ahead and spec the Heavy Haul with the following “RULES OF THUMB” based on your customer request and axle rating. A D40K axle is good to 160K GCW (DSP40/41 only good to 110K GCW), D46K - 200K GCW and D52K - 240K GCW SISUs - 330K GCW. Now, this has nothing to do with cooling, or gearing/startability. Customers are always reluctant to document what they are really going to pull/push and you can pretty much guarantee it will be more than what they indicate.
Heavy haul GCW
Some sales tools artifically cap the GCW that is documented on the sales order. Today insurance and bonding companies can require GCW documentation to size the power units with the correct number of chassis. For example, 600K load would require 3 chassis rated at 200K each. If you use a reduced value (say 110K due to a product approval), then with this example, the customer will require 6 chassis, costing the customer money.
FW35 vs. FW2570 5th wheel
If your customer is a heavy haul utilizing a 20-23K pusher, you should use the FW2570 vs. the FW35. Holland rates the FW2570 at 70K vertical loading. The FW35 is good for 55K. Most heavies are permitted to 20K per axle, so that would put 60K on the wheel. Both are rated at 150K drawbar pull.
Bendix eTrac
This option automatically drops air out of the rear-rear axle when lightly loaded. Make absolutely sure that if you spec with a 6X2 (6 outer ends, 2 driving) you request this option. There have been many a tow bill paid to pull the truck a few inches. If you make this mistake, eTrac can’t be added later. You could replumb the suspension locally, (not a factory option) to drop pressure out of the rear rear axle, but then you risk the driver actuating when fully loaded, stressing the fwd-rear axle components past the creep ratings, leading to outer end failures.
Ultrashift creep mode
Allows the transmission to slowly move the truck forward or reverse smoothly. There are no significant tradeoffs for having the feature enabled, but there are some fleets that don’t want it, due to specific application/operations. I would say it is quite rare that a fleet doesn’t want creep enabled.
Ultrashift Plus LAS vs. VAS
You can’t reprogram LAS, or VAS transmissions at this time. Contact your local Eaton rep to determine if the LAS is acceptable for a non-linehaul STOCK truck or you ordered for the wrong application, or the customer changed his haul. If a customer runs into issues because the transmission was mis-represented, Eaton could cancel the warranty. The VCS, MHP, VHP, MXP VMS, and VXP’s are stand alone and cannot be reprogrammed. LAS has a 5 year 750K mile warranty for linehaul only VAS has a 3 year 350K mile warranty for regional and minor off road applications such as a bottom dump or end dump.
15-spd transmission
If your customer is looking for a really LOW 1st and LOW Reverse gear, you might consider the 15-spd transmission vs. an 18-spd.
Overflowing fuel tank
Since some fuel system utilize a restricted (crimped) return with Tee fitting, another possibility for issues would be a contaminated return/s. Previously, the issue was only on the suction side, however given this design, any chunks at the return line restriction could cause an imbalance. These systems can be temperamental, so any partial restriction would cause an issue. This is a 6.9mm hole (1/4”. Please share with your shops, to add to the check list.
Non-CDL Class 6 rating axle requirements are
DEF tank sizes
Due to the limited frame space availability in many configurations there is no common advantage to over specifying the size of DEF tank required. DEF is heavy and some tank sizes result in very odd aesethical layout. This is due to the d-shaped top of the tank, it interferes with some other components that are not specifically noted on the sales order.
Disconnect switches
Do not assume that battery disconnects are safe to use to shutdown the engine (old school).That wiring is there for the shutdown cycle and isn’t intended to keep the engine running with disconnects off – but if someone does activate the switch, it would keep the engine ECM active along with the after treatment system. It’s HIGHLY recommended that no one do this in that damage could occur, so make sure everyone shuts the truck off using the ignition key, then wait a couple minutes to allow the DEF fluid to purge from the line, then disengage the disconnect switch. If you don’t wait the 2 minutes, DEF can remain in the pump and freeze.
2-spd auxiliary transmissions
The new Namco NM 203H 2-spd was designed to replace the AT1202. The major difference between these two is torque capacity. The AT1202 is good for 17,500 lb ft, the NM 203H will accept 31,000 lb ft. The FAT 30 was designed to compete with the APO 1750 4-spd on chassis grossing greater than 240K. There is a significant price difference between these boxes, so determine what your customer needs.
Automatic Traction Control (ATC)
Do not spec ATC as a substitute for crosslocks in off highway conditions.
Fuel economy
Tire condition (air pressure, thread thickness) make biggest difference in MPG below around 50 mph; aerodynamics is the most important factor over 50 mph.
Tail lights
If you don’t spec a tail light, the factory will install a set of inexpensive lights for transport. If your customer or body builder will install their own, this will save you a buck.
Road usage
Make certain you ask the customer if the percentage of off-road usage is time or miles. The two do not correlate.
Extended service components
Some common components, usually requested for linehaul, would include Meritor drivelines (lubed for life), standard (non-greaseable) spring pins, air disc brakes (generally last twice as long as drum brakes), brushless alternators (no brushes to wear out), AGM (non-Optima) batteries (gel filled, absorbs vibration better), and Self-adjusting clutch, using the air restriction gauge or under the hood pop gauge (determine the optimum time to change the element).
Air cleaner servicing
Two of the most common air cleaner servicing problems are: 1. Over-servicing: the least efficient time in life of the filter is when it is new or when it collapses. Filter elements increase in efficiency as dust builds up on the media. 2. Improper servicing: your engine is highly vulnerable to abrasive dust contaminants during the servicing process when the filter is removed from the housing. A leading cause of engine damage is due to careless servicing procedures. ( Also look at If you are having oil changed at the local Mr. Lube, DON’T fall for the common upsell of, your air cleaner is dirty, how about I install a new one. That’s a common upsell that is not doing your engine or your pocket book any favors. Now, if you’re running in the dirt, then by all means have it checked.
Vehicle Verification Letter
Various State and Federal Agencies under some circumstances require certain written documentation describing how a particular vehicle was manufactured or if there are any outstanding Federal recalls. The Original Equipment Manufacturer (OE/OEM) or an authorized agent of the OE is typically the only entity that can provide this documentation. This letter is common for import purposes. It can be ordered at some dealerships through their parts department. It’s called a Vehicle Verification Letter. You’ll need to fill it out and Parts will either fax or mail you the letter(s) when completed.
37.4 compressor and Everflow air dryer
If your customer requires the large compressor, but wants to use as a bulk unloader w/wet air, the large dryer is not required. If in a heavy haul application, review the Bendix Air Dryer Application Guideline chart to determine if the Everflow is required. If the answer is yes, then the 37.4 compressor is required as well. Neither the GCW or number of trailer axles alone control these components.
Tire diameter calculation
To compute the approximate size of an 11R22.5: Tire sidewall height = 11 inches (tire width) X 90% (tire profile) X 2 (two sidewall sections, one above the wheel, one below) + 22.5 inches (wheel diameter) 11 X .90 = 9.9" X 2 = 19.8" + 22.5" = 42.3". In low profile, a more modern metric sizing is used: i.e. 295/75R22.5. Here, the width (295) is expressed in millimeters, the profile (75) is included in the size, and the wheel is still shown in inches (22.5) To compute the approximate size of a 295/75R22.5: Convert the metric width to inches (295 divided by 25.4 = 11.6 inches) then compute the same as above - only use a profile of 75%. 11.6 X .75 = 8.7" X 2 = 17.4" + 22.5" = 39.9".
Tire width vs. rating
Just because the axle, springs, steering gear, wheels, hubs, and tires can support 20K, doesn’t mean the state the truck operates in will support the rating. There are many states that use tire width to determine weight allowed. Make sure you look at the state regs. For example, California allows 620 lb per lateral inch of tire width, some states are 550, others up to 700 lbs, so do your homework.. Example, 315 tire is 12.4’ wide X 620 = 7,688 lbs X 2 = 15,376. 385 is 15.16” X 9,499 X 2 = 18,800 lbs. 425 tire is 16,73” wide X 620 = 10,374 X 2 = 20,748 lbs. If ya come to the Vocational Class, we’ll give you a book that has this state bridge information.
Single vs. dual tire ratings
The main reason that dual tire load limits are set at a lower rating than single tires is that tires paired up as duals do not always contact the road surface equally. Examples of this would be ruts in the road surface, climbing over curbs, mismatches in inflation pressure and/or remaining tread depth, to name a few. This unequal road surface contact results in one of the dual tires ending up carrying more than its fair share of the load. In order to provide a “safety cushion” for when this happens, the maximum weight allowed is set lower than for a single application.
Steerable tag axles
Tags are located behind the drive axles. The lock out sometimes must be plumbed in the aftermarket. This feature helps stabilize the chassis and keeps the tail from wagging the dog. If the truck has a manual transmission, your shop could plumb to the high/low range valve on the transmission With Allison, there is a speed signal wire, the shop could tie into that with a solenoid. Some truck models have a programmed speed that could be connected as well (suggest 25 MPH as a default). Another thought is to lock the tang when backing on a separate switch in reverse. The tag takes allot of abuse in reverse, since the caster is designed to go forward. If you have an air ride suspension ask the shop to add an over inflation valve w/dash switch to be used when backing to help raise the lift axle out of the dirt.
42” trailer gap
There is no way you’ll be able to achieve the desired 42” trailer gap (measured from the sleeper back panel) with single or dual exhaust up the sleeper back. That exhaust can take up to 20” (with grab handle) and is just too much to permit the 5th wheel to slide far enough forward, so your customer will sacrifice a bit of fuel economy.
Fuel tank size
Our habit is to spec 120 gallon RH side, and 110 LH or both larger. With chassis getting 7+ MPG these days, that’s 1610 miles, plus 1610 lbs, along with forcing the larger DEF tank at 9 lbs per gallon and the added frame space. Let’s say the driver averages 55 MPH for 11 hours, that’s 605 miles. Given that, the truck could easily operate two days between fill-ups. You might ask if smaller tanks are warranted. Dropping 10 gallons of fuel would also reduce the minimum size of DEF tank required, again saving money and weight.
Tire speed
Tire speed assumes full load. Heat is affected by speed, load/inflation, and design/construction. Consider the M843 designed for on/off highway, while the R250 is designed for on-highway. The M843 tread depth is 26/32nds, while the R250F 19/32nds. The deeper the tire's tread depth, the more heat is generated and held within the tire as it cycles through its footprint. The biggest difference between the two tires is the rubber compound and tread. The R250F, for on-highway, uses a cooler-running rubber compound. Since the M843 requires a deeper tread depth and tougher rubber compound to do its job properly, the only way to compensate for the extra heat is to limit its speed.
Alternator warranty
Rule of Thumb, you’ll get more amperage out of a brushed, but the warranty is less, so it’s a tradeoff. Brushed are usually 2 yr, brushless 3 year. Check with your manufacturer for details.
Standard mixers
These are state/area specific mixers, (not boost-a-load/flying tag). This body (depending on barrel manufacture) can have issues with frame deflection depending on the rear pedestal design and position with a single 11 5/8” frame. The rear pedestal can rotate rearward positioning the rollers off the barrel ring with a full load of mud. There are body builders who can and will build with a single 11 5/8” rail without insert (preferred design). That is one heck of a cost and weight savings vs. a 10 ¾” with insert. It doesn’t matter if you or the customer are working with the body builder, make sure someone communicates what’s needed and spec’d so if knee braces are required, those are figured into the barrel pricing up front, not after the chassis and barrel are mated.
Mixer EOF cutoff/overhang/after frame
Standard mixers use 80”, Bridge Formula use 110”. With the inserted 10 ¾” (Standard mixer) you’re now paying for a longer frame rail block which will be cut off and added to the Christmas Tree Fund (body builder iron pile).
Federal Bridge Formula
Are the outer roads of the Interstate highway system considered Interstate highway? YES, along with under and over passes.
I’d highly recommend 4 batteries to support to functionality.
AGM Batteries
Absorbed Glass Mat (AGM) batteries have many advantages over traditional flooded-cell batteries. They are very vibration resistant, offer good cold cranking performance, and have lots of reserve capacity for running sleeper lights and accessories. However, AGM batteries are sensitive to a deep discharge. Once they reach a fully out of charge state, it’s difficult to bring them back without a trickle charge for 24 hours using a special charger. Therefore it’s strongly suggested you spec the LVD low voltage disconnect. This includes the Optima battery inside the cab. These batteries should be charged with a voltage-sensing charger that will prevent overcharging and boiling the electrolyte.
Either can be used with spark ignited engines. Every state has a responsible group to determine requirements (example State or local Fire Marshal, Railroad Commission, Local Fire Dept, etc) for who is responsible for facility and service training. CNG tanks have different rules and regulations than LNG. Often dealers sell the system and then are not equipped or certified to service at their facilities, the customers facilities, or for another dealer where the truck operates..
Progressive Shifting / Gear Down Protection
Progressive Shifting is more effective on chassis which do a lot of shifting (non-line haul) in town, driving hills on secondary roads. Gear Down is effective for line haul and interstate driving, or basically any driving where you utilized the top two holes. For the most part, I would NOT recommend either of these fuel saving features on vocational applications or high HP engines including pulling a bull wagon and owner operators. These can be a driver dissatisfier.
Meritor MFS20
Kingpins are 3” wider than the D2000 Dana axle. Given that, when specing the 425 tires with 12.25” wide wheels, it would be important to spec the 5.81” offset wheels, not the 3.88” that people are accustom to with the D2000. The 3.88" offset wheels are used with Dana 20K axles to acheive the best turning radius. The MFS20 wheel cut will be similar with the 5.81" offset.
Shortest wheelbase. for Federal Bridge
For a single rear axle there would be no issue 12K + 20K = 32K. 34K is a tandem which is good between 40” to 96” so any wheelbase would work. Here is 52” axle spacing and 34K rear. Subtract 1” off the wheelbase for 54” spread. 12K steer would be 124” w.b. (13’ = 12.5’ bridge). 13.2K steer would be 148” w.b. (15’ = 14.5’ bridge). 14.6K steer would be 172” w.b. (17’ = 16.5’ bridge). 16K steer would be 196” w.b. (19’ = 18.5’ bridge). 18K steer would be 220” w.b. (21’ = 20.5’ bridge). 20K steer would be 256” w.b. (24’ = 23.5’ bridge). 46K and 52K rears match the WB above. Federal bridge only allows 34K on the drives, so the same values above would apply.
Remote clutch lube station
I have reason to suspect these joints are not fully greased out of the factory. To do so, the factory would have to have someone under the chassis to observe when the grease purges (which can’t be done on line). The zerks on the remote station appear to be greased, but probably were only given a couple shots. I’d recommend your shop or customer fill the lines prior to putting the truck into service, it’s a two person job. Without this option, the greaser has to find the clutch points (up to 5), some of which are very difficult to access, specifically the cross shaft.
Heated fuel filter
If you spec a block heater, why wouldn’t you spec a heated fuel filter? If it’s cold enough to warrant keeping the coolant/block warm, wouldn’t you think the customer would want to thaw the ice in the filter and help keep the element clear of wax particles?
Rear Shocks
“Rule of Thumb” if the body weighs less than 7,000, then shocks are recommended, thus if you build a tractor, you should always spec shocks. Washboard roads also require shocks. Regardless if you don’t spec shocks on the Chalmers, it comes standard with lower shock brackets on the walking beam, so a customer might ask why you didn’t install shocks.
Allison PTO’s
If you are having difficulty with 8 o’clock PTO clearance position on an Allison, you might consider the 890 Chelsea. It has a smaller cross section at the mounting point (10 bolt on the 3 and 4,000 series) and moves the pump joint to the rear of the transmission where there is more room. It’s expensive, but so is not getting the deal. Allison’s have PTO ports in many different locations, so do your homework.
MFS20 Meritor axles
MFS20 Meritor axles: The 3.88” offset wheel will give you 105.5” wide steer axle. NOT GOOD. Beam KPI+2*KPI to flange-2*(inset of wheel)= track. Track+ width of 1 tire= theoretical outside to outside
Wire braid chassis hoses
From my experience, this option isn’t what it’s cracked up to be. This option is very labor intensive. There is a bit of artistry required on the factory line, plus the workers used to have more time to accurately measure the line lengths. I’ve also had instances where on gravel roads, the rock attack the lines, wearing them to the point of leaking. The nylon line is much more forgiving and the line knows exactly what’s required to build.
Pusher/tag controls
Option for Tag/Pusher Susp Controlled by drive axle air bags, plumbs into any suspension air bag pressure. This switch (set at 5.5 lbs) controls the lift axle proportioning valve. This does not control when the lift axle is up or down. This function is still controlled by the dash switch, chassis park and reverse functions as all lift axles do. The only difference is the lift axle regulator is removed and replaced with a proportioning valve an this pressure switch. No one seems to know if this proportioning valve can be set to within 10% of the variable suspension ground loading on a heavy haul as is required in a number of states (California, Missouri, and Oklahoma are three that I know of). If you require the 10%, I’d recommend normal controls and have your shop or body builder install an ACK 124 Watson valve. It does ensure the 10% ground loading.
Heavy hauls
I receive numerous of calls on chassis already built pulling multi-axle/jeep trailers. Note that the 46K axles are generally good to 200K 6% grades, 52K rears to 240K both values on paper. The absolute FIRST question for a heavy haul customer is what is his GCW! If your customer requires larger than 240K, then you have to look at SISU drive axles, but before you do that, please contact me and we’ll discuss the customer’s needs and what other customers actually do. Changing the chassis after it’s built doesn’t serve the needs of the customer, or your billfold. Get me involved early, I’m here to help.
Tri-drive axles
The tri-drive for Meritor and Dana don’t increased GCW over tandem axle installations. Therefore the T69-170 are made of three 23K rears (two are good to 200K, as are three) and the T78-190’s use the 26K rears (two are good to 240K, as are three). Make sure your heavy haul customer understands the ratings of the tandem and tridems GCW are the same. Tridems are good for pulling off road, plus some states and Canada like this combination for heavy hauls for increased 5th wheel loading. Remember, the benefit is additional traction, not GCW.
Battery maintenance
As you probably know, computers (ECM’s) and certain electrical components add parasitic (draws current) load with the engine shut off. Batteries should be at least 80% charged in the factory, which in layman’s terms equates to around 50-60 days of sitting, before dropping to unacceptable levels. As the ambient temperature increases, this life shortens, so battery maintenance on stock trucks is important. Batteries are like people, they like cool/dry mild temperatures. It also doesn’t help to leave interior lights on (not shutting the door completely which continues to power the CECU), radio, refrigerator, engine cranks, etc. You might want to give thought to charging the batteries which have been sitting for 4-5 weeks or adding a solar charger. A good preventive maintenance practice would be to charge the decked trucks since they have not had a chance to completely charge the batteries since leaving the factory, like the horse does. Battery Disconnects helps increase life since there is no draw while the batteries sit.
Green House Gas odometer change
Mileage is recorded at the time the chassis is built, and odometer mileage is updated to the chassis record each time a programming tool is plugged in. If the CECU has to be replaced the vehicle odometer will show zero, but the chassis record will show mileage from the last time the vehicle was in the shop. Customer Service can access this record and add the chassis record mileage and replacement CECU mileage to get total mileage. Customer Service is authorized to add mileage to allow for time since the last update. This is all to support GHG requirements for definition of vehicle life and expiration milage from some Emission Controls (VSL and EIST).
Aerodynamic fuel economy 'Rules of Thumb" from Cummins
Every 2% reduction in aerodynamic drag results in approximately 1% improvement in fuel economy. Above 55 mph, each 1 mph increase in vehicle speed decreases fuel economy by 0.1 mpg. Worn tires provide better fuel economy than new tires, up to 7% better fuel economy. Used lug drive tires can get up to 0.4 mpg better than new lug tires. Ribbed tires on the drive axles provide 2–4% better fuel economy than lugged tires. Every 10 psi that a truck’s tires are underinflated reduces fuel economy by 1%. The break-in period for tires is between 35,000 and 50,000 miles. Tires make biggest difference in mpg below around 50 mph; aerodynamics is the most important factor over around 50 mph. The most efficient drivers get about 30% better fuel economy than the least efficient drivers. Idle time is costly. Every hour of idle time in a long-haul operation can decrease fuel efficiency by 1%.
Creep rating
Creep ratings refer to the impact of weight added to the front and rear axles on a chassis when a liftable axle is in the raised position. Lift axles are typically up when the vehicle is off paved surfaces on a job site. Vendors understand this situation occurs and have assigned a weight value that exceeds nominal capacity to their products.
Hydraulic assist front drive axle
If you are interested in this aftermarket option, make sure you order an Allison transmission WITH PTO provision, NO -HS versions. Truck remains as built frame height and length (great for bucket trucks and any vehicle with height and short length restrictions). Front/rear tire sizes can be changed after the truck is built and the system adjusted accordingly. When you first start out in assist mode, the steer tires turn faster than the rears to promote directional steering in the slop. Only works at or below 20MPH with on the fly shifting, freewheels above this speed. It’s less weight than a transfer case setup. You won’t save any money, but it could be a nice alternative to a transfer case/front drive axle. The agriculture folks have been using hydraulic drives for decades. This system’s duty cycle is 10% so don’t use it if the customer needs allot of front wheel drive. Terra Drive Systems 9098 W. 800 S.Brookston, IN 47923 Phone: 219-279-2801 Toll Free: 800-348-2474 Fax: 219-279-2390
DEF dosing
There seems to be a number of rumors on usage. When DEF fluid first started in 2010, usage was in the 2% range. Since that time, the requirements for cleaner emission have ramped up and dosing rates have as well. Typically there is no dosing the first hour of operation and the rate is dependant upon the ambient temperature.
Air suspensions w/service body
This is not a good idea if the box has an offset RH crane. This crane applies extra weight to the passenger’s side. Most body builders add a second leveling valve to make up the difference. The right side bags on some suspensions can’t handle the added weight and has a tendency to blow.
Allison 4xxx w/PTO
Allison 4xxx w/PTO provisions at the 1 and 8 o’clock positions, 10 bolt. Most body builders use the 8 o'clock position because it’s easier to get to, but then encounter lower frame flange interference. Some body builders find it quicker to raise the RH side of the cab or remove the passenger’s seat for mounting at the 1 o’clock position. If you are going to use this location, make sure you opt for the optional dip stick mounting.
Fuel coolers
Remember the engine sends really hot fuel back to the tank/s, but at a reduced volume from the old days. Today not all engines require a fuel cooler with a single tank, so don’t call it out if you don’t need it. Remember the cooler works all the time even when it’s -30F. It’s located in front of the radiator, with NO thermostat, so it always has nice air flow, especially with the 2-sp fan hub.
Make sure this forklift stays within the state bridge length. Sometimes, the driver will have to turn the single steering wheel on the Moffett to stay within the overall length. When they do this, it’s important to have enough ground clearance to keep this from occurring since the wheel is perpendicular to the truck travel. A level bed is always advisable. There is a spec from Cargotec on the rear axle location, and looking at federal bridge, you can do your customer a favor: It is hard getting weight on the front axle on these trucks. A 280" wheelbase on 24.5ft bed, took the federal bridge from 58500# to 59500# vs. a 279” with a 52” spread. In states that don’t recognize the pusher, there is about 3” more wheelbase you can have with a Moffett kit anyway. It’s about 1” = 400# shifted to front axle in this case.
Turning radius
Customers normally prefer the tightest turning radius/wheel cut they can get, especially with set forward axle chassis. You might consider asking your shop or whomever is doing the PDI to check the axle stops. Now, warranty won’t pay, but prior experience indicates that the stops are not as close to spec. as they could be. Remember, the factory cycle times are fast, so nailing this consistently is difficult. Turn the wheels to a full right turn. Note the position of the tire relative to the steering gear or drag link. Adjust the stop bolt on the right spindle until a clearance of 1” (or the OE spec which can be ¾”) is maintained between the tire and any part of the chassis. Then repeat for the left turn.
LX driver’s seat w/leather
The seat cushion foam and the seat back foam have small fans built into. Includes fan in seat base and back of seat as well as heater—switch operated. This is not connected to air conditioning. These fans blow ambient temp through the perforated holes that are in the middle of the leather seats. This results in the seats feeling cooler.
Rear axle temperature sensors
You might rethink using the rear-rear axle temperature gauge on a dump truck. These trucks are always backing into rock piles and driving on undulating terrain where the sender can easily be knock off. Given that, you might consider putting the gauge only on the forward rear which is probably the best axle to note temps from anyway given the interaxle differential is located there.
Removing ESP on a used truck
If your customer wants to remove Bendix Electonic Stability Program (ESP) or Wabco Electronic Stability Control (ESC), they will need to replace the ECU from an ESP/c version to a premium version with traction control or a standard ECU with ABS only. Pulling the fuse will disable ABS also. We do not recommend removing the fuse.
Engine idle shutdown timer (EIST)
With this feature enables and the truck is idling, when the engine is 30 seconds away from shutting down, you’ll get a shutdown light. If you don’t want it to shutdown, all you need to do is tap the brake, actuate the clutch or hit the throttle and that will reset the clock. Default with park brake applied is 5 minutes. Without park brake, it’s 15. You can program different times.
Multitorque engines
These engines have two torque ratings. Remember, the higher ONLY occurs in the top two gears. On a 10C transmission, in 8th gear or less, the engine is pulling at the lower torque rating. For these reason straight torque is preferred when pulling long and or steep grades. Today, OEs are looking at making this the top three gears.
Creep Rating
We always think of Creep/Site as calculated with lift axles, however if you have a heavy haul pulling a jeep, there is a good chance they will drop the dolly/jeep when they get to the job site. It will be important to ask the trailer manufacture what the kingpin load will be without the jeep.
Sheppard SD Gears
Previously, if you have lift axle/s that resulted in an altered creep calculation in the 28K or higher range, you should spec dual TAS85 TRW gears because they were rated above that value. Sheppard also has a gear rated that high. According to TRW’s website, the dual TAS85 has 58,850 in-lbs of output torque (at 2175 psi). The dual SD110 has 59,760 in-lbs of output torque (at 2756 psi). All other things being equal SD110 gears will perform as well as the TAS85 gears.
The driver can hold a Class B license and pull a trailer, just as long as the trailer is not over 10,000 pounds. A combination vehicle may weigh more than 26,000 lb and not require a CDL. Example, tractor weighs 26,000 lbs pulling a trailer weighing 10,000 lbs, total GCW 36,000 lbs does not satisfy the federal requirements needing a CDL. One more pound on either requires it. Whether a vehicle has air brakes does not affect whether a CDL is required, however there is a license restriction if the applicant either fails the air-brake component of the knowledge test, or performs the skills test not equipped with air brakes. Shop test drivers: requires a CDL if the vehicle is operated on public highways.
Manual clutch with hydraulic assist
Without a self-adjusting clutch Eaton recommends a tech under the truck, pulling the inspection cover and checking the gap monthly. The manual adjusting style continues to be the standard due to the lower price point, but think of the customer. Eaton quotes 17 adjustments over the lifespan of the clutch (time and money)... this contributes to the actual benefit of self-adjusting product.
Bridge Formula
The most important value is the overall bridge regardless if it’s a straight, or combination. That’s the absolute maximum legal weight possible. You still need to calculate the inner bridges, because they can reduce that value, but if you’re trying to determine how much weight will be applied to the lift axles, the overall bridge will give you a good idea where to start. Come to the Vocational Class if you’d like to know more about state and federal bridge.
Chassis Weights
If you take a new truck to the local scale to verify weight, make sure you stick the tanks to determine fuel weight and subtract. Chassis weights on the door sticker are as they come off the line with NO fuel and NO driver. Factory scales are certified once a year.
Overall length requirement
Every state (except Georgia) has an overall full truck length requirement. The majority of states are 40’, so keep this in mind when specing a boost-a-load (flying tag) chassis for the second owner and which state they operate in. Also, don’t spec the fixed center tow hook on these chassis. Measurements are to the extreme features, so that will add 4-5”. Now, if you spec the two removables and leave them installed, those are fine because they are considered “removable”. Go figure.
Deactivate ATC switch
If this is available its highly recommeneded with crosslocks, and/or off road applications. (Remember, Ultrashift plus forced ATC due to the hill hold feature). You can turn the ATC off so that it doesn’t conflict with locked axles or off road conditions. Make sure the driver’s understand, it will deactivate the hill hold feature in the off position. Use the standard ATC switch to turn that system off. Remember ATC doesn’t operate above 25 MPH.
Body/Trailer Builder
Just worked on a chassis grossing 105,500 lbs. hauling 68,000 lbs of acid. We worked with 2 trailer manufacturers, one with 4 axles, the other 5, resulting in two totally different tractors. Trailer manufacturers are good about making recommendations for wheelbase and ground loading to meet the bridge formula, but it’s up to you to verify if these values are something we can build per the customer specifications which includes your tractor under their trailer. Most of the time, you can’t build what they have indicated, so you must work together on resolving the weight and axle distances. It took 2 weeks of back and forth negotiations to finally arrive at a compromise 5th wheel position and chassis weights/specs that worked. Tractors can pass bridge, trailers can pass bridge, but when coupled, more than likely they won’t. No use ordering a tractor that won’t work. I would be happy to get involved and help you arrive at a solution.
Ultrashift transmission PTO engagement - mobile
Mobile PTO Operation The Transmission countershaft PTO is used in this application and provides limited mobile operation in the start gears. To engage the PTO for mobile operation perform the following steps: 1. Depress service brake. 2. Release parking brake. 3. Select “MANUAL” on the Shift Control (this stops countershaft rotation for PTO engagement). 4. Select the transmission PTO switch. 5. Select “MANUAL”, “Neutral” or, “Reverse”, as required for vehicle movement. 6. Release service brake. 7. Raise engine speed to move vehicle / operate PTO. Remote throttle controls are not approved for use with UltraShift.
Fuller LSE
LSE stands for Linehaul, Small-step Efficiency and was originally designed for Navistar. The LSE 16-spd has 200 RPM splits (much like a 18-spd), vs. the 400 RPM for 10-spd transmissions. The reason why it appears to have the same splits as an 18-spd is because it IS. The top two holes are blocked making it a direct drive. They build F (direct drive) and FM (direct with Multitorque) series. Designed specifically for linehaul applications. It has small ratio steps between all 16 gears to spend more time in the most fuel efficient engine RPM band, resulting in enhanced fuel economy. It also has 4 reverses. Interesting concept. Contact Eaton about the warranty.
14.6K heavy hauls
Be aware, the creep rating on this axle is 20,440 lbs. Dana and 21,900 Meritor, so the axle is designed to handle the added weight of raised twin 13.5K pushers or one 20K-23K lift axle, however there is no steering gear that can handle that weight. Spec the largest gear and spring possible. Both will be affected with the lift axles up with this combination.
Ultrashift transmission PTO engagement - stationary
Stationary PTO Operation The transmission countershaft PTO is used in this application. To engage the PTO for stationary operation perform the following steps: 1. Apply the parking brake. 2. Select “D”, “MANUAL”, or “LOW” on the Shift Control (this stops countershaft rotation for PTO engagement). 3. Select the transmission PTO switch. 4. Select “N” on the Shift Control. Split Shaft PTO Operation (Stationary Only) To engage the transmission for split shaft operation, perform the following steps: 1. Select “D” on the Shift Control. 2. Select PTO switch.
Long stroke brakes
Long stroke are designated as a 3”, stroke, vs. a standard 2.25 or 2.5”. Some have square raised air ports, long stroke trapezoid tags, embossed 3” in the pressure cap, etc. You can’t legally mix and match, it will effect performance and timing. The key advantage of the extra stroke length measured from the actuator's unapplied position to full extension, is that it keeps brakes in adjustment longer, reduces out of adjustment citations and improves brake efficiency.
Leaning 3-axle Standard mixers
This issue is usually encountered on set-back 3 axle chassis, not Bridge Formula mixers. Not that its exempt, just that the 3 axle chassis are more susceptible due to weight distribution. (20K on a Standard steer axle, 19K on a Bridge steer axle). This issue also seems to be customer related. Determine if a customer utilizes a dry vs. wet batch plant, then ask to check mix calibration. Seems if water is added at the wrong rate/time, with certain mixes/slump that the barrel experiences “Nose Packing”. This formula sticks material to the nose of the barrel, thus over loading the steer axle. Once the buildup is present, the barrels must be chipped to resolve. To determine if this is a possibility, weigh the front axle, left to right loaded. Normal weighs are in the 9K range on the right, and 11K on the left. If both are higher, then “Nose Packing” could be present. Some customers weigh chassis regularly to determine buildup and when to chip in an effort to determine which drivers are not properly cleaning the barrels, so this too could be an indicator. Let me know if you find this issue.
Reversible fans
If you are designing a chassis to operate in a (course dirt/agriculture) environment, you might consider a reversible fan. No, the fan doesn’t change direction, the hub rotates the blades 180 degrees and turns the fans from a sucker to a pusher. Reversible fans can reduce maintenance and related downtime—as well as help avoid the potentially costly consequences of overheating—by periodically directing a reverse blast through radiators, oil coolers, air-conditioner condensers, and intake screens to purge debris. This is not a factory option, but CVS or your shop could/will install. Just like everything, these fans are not as efficient as STD sucker fans, it’s a tradeoff. Some manufactures are Cleanfix, Phillips & Temro, Flexxaire.
Allegro V2B cap
This is a tire cap which protects the valve stem valve plus you don’t have to remove to check the pressure or to air the tire. Given air pressure today is a big deal for fuel economy, this sounds like a novel idea. Anyone know how they work?
Wide base tires
If you spec with duals, and the customer replaces with wide base/super singles, just to have the duals reinstalled at trade time, make sure you spec Rear Brake Camshaft Reinforcement AND Gusseted Cam Brackets, if available. Wide base tires require these to keep the S cams from cracking. It’s probably not a bad idea to add them to stock units as well, just because no one knows if the customer will change. It doesn’t hurt to have them, just more money. Also call out the =>11mm axle housing, example, DSP41.
20K steer axle turning radius
If you want the shortest turn possible with a 20K steer, you might ask Applications to run a turn radius calculation comparing the two axle manufactures if nothing appears in the Turn Radius Workscreen. The D2000 and 3.88 offset/inset Alcoa wheel is 103” overall width compared to the MFS20 with 5.81 offset/inset wheel (101.7” wide). The radius difference was 39.4’ vs. 44.1’ in one a recent comparison, with the D2000 turning the shortest. That’s a 9.4” different diameter.
Lift axle disc brakes
I would not recommend disc brakes on lift axle/s. Usually, they are the lightest loaded axle on the chassis so inherently they lock up and flat spot tires. The LQ-5 valve will help with flat spotting, but this is not a factory installation. The LQ-5 is an air pressure limiting valve for lift axle brakes. It drops application air pressure (approximately) in half, thus helps with lift axle wheel lockup (flat spotted tires). For example, with a 40 psi foot pedal application, the lift axle brakes 20 psi. Full application pressure is passed though at full pressure. Use only when pusher axle ground load will never exceed approx. 60% axle rating.
Trailer height
I just looked at Great Dane’s Refer and Box trailers and all require a 5th wheel height (Upper Coupler Height) of 47”. That puts the top of the trailer at 13’6”. Make sure when you select you rear suspension, frame height, and tire size unladen, 5th wheel height, that you spec a 5th wheel height no more than 47”, or check with you customer for this dimension. Calculate unladen height for worst case scenario.
Jost 5th wheels
The JSK 36N is a light weight fabricated plate rated at 45K vertical loading. The JSK’s 37U is cast and rated at 50K. All three have a drawbar pull of 150K. To envision this drawbar pull, lift a 150K truck/trailer hoisted vertically via a crane. Pretty impressive.
SL2200 dual tire steerable
Yes a dual tire steerable lift axle exists from W/C. If you want 4 aluminum dual wheels, the tires will be over 102”. If interested in staying below 102”, then spec steel wheels with any drum. I ran this calculation with 295/75R22.5.
Feedlot trucks
The reversing fans are meant for high rpm but low speeds and not for long distances (feed lots). One setup used on feed trucks instead of the reversible fan, is a low fin density radiator, removing the A/C condenser and adding a frame mounted Red Dot HVAC to the right side, putting a wire mesh screen on the front of the charge air cooler/radiator to reduce debris, and just running a standard factory fan. It has been working fine. Without a reversing fan, the radiators will need to be blown out daily and washed out weekly. They also have to take special care of not bending the fins on the radiator or charge air cooler.
Tire wear on dual mounting with uneven pressure
Old School Rule: Perfectly mated dual tires with a PSI difference of 10 lbs (100 psi pressure in one tire and 90 psi pressure in the other) will result in tire wear equivalent to the lower pressure tire being drug 10 feet for every 50 miles of travel. 90 psi is not a flat tire, no magic hammer possessed by a driver can detect this difference. The increased tire wear is significant. Excessive tire wear is a controllable cost. USE A GAUGE to eliminate this potential money waster.
Landing gear location
We’re always trying to figure out how close we can couple the nose of the trailer to the BOC, BOS, Headache rack, Back of Natural Gas Cabinet, etc in attempting to achieve 42” or less. Great Dane places their gear at 98.5” for the 48’ and 53’ van trailers, and 105” for the Refers from the king pin. Their flatbed is located 112”. Given these variables, so you need to be asking the customer this value, then plug the numbers into Super Tractor Calculator to determine how far forward the 5th wheel can be placed. .
Heavy haul trailers
When a trailer manufacture talks about a 55 ton trailer, that is only the capacity of the trailer and has nothing to do with what tractor is pulling it. Many trailers are used off road, thus weight per axle on the highway is not a concern.
ATC vs. crosslocks
Generally speaking, the ATC was designed for on road and crosslocks off road. Many customers are fed up with crosslocks because of expensive failures since the drivers don’t understand how they work. Decision makers would prefer to replace brakes more often and suffer the related ATC performance issues, as opposed to the repairing broken rear ends. You need to have that discussion with the customer as to the pros and cons. Remember what you learned in the Solutions Class to explain the differences.
16-spd Ultrahift LSE
These are 18-spd automated transmissions with the top two overdrives blocked. The RPM step between the gears is smaller, and occurs throughout the range, improving fuel economy for those who go through gears frequently.
Weight distribution
Once you determine your axle loading a CG analysis will tell you what point on the rail will achieve your desired ground loads. If that position is ahead of the bogie/trunnion, then you are moving weight off the rear to avoid overloading that axle group. If the position is behind bogie/trunnion, then you are moving weight off the front axle to avoid overloading it. See the Super Tractor Calculator.
GCW (Combination) weight for a tractor includes the trailer so is always greater than the sum of the axle values (GAWR). Don’t just add the axles capacities together as you do with a full truck. For example, if you had a 20K steer, 20K lift and 46K drives, that would be capable (depending on gearing) to pull around 200K GCW. If you had a full truck (Vehicle - no trailer) then 86K GVW is your maximum.
Retarder brake control
On surfaces with low traction, application of the retarder can lead to high levels of wheel slip at the drive axle wheels, which can adversely affect vehicle stability. To prevent this, the ABS controller switches off the retarder as soon as a lock-up is detected at one (or more) of the drive axle wheels. When the ECU is placed in the ABS off-road mode (on vehicles equipped with this option), it will switch off the retarder only when ABS is active on a steer axle wheel and a drive axle wheel.
ABS w multiple trailers
This configuration may reduce the effectiveness of Stability Systems. ESP is designed and optimized for trucks and for tractors that tow single trailers. If a tractor equipped with ESP is used to power multiple trailer combinations (known as “doubles” or “triples”) the effectiveness of the ESP system may be greatly reduced. Extremely careful driving is always required when towing doubles or triples Excessive speed and aggressive maneuvers, such as sharp turns, sudden steering inputs or abrupt lane changes should be avoided.
Log book requirement
A driver is exempt from Log Book Requirements if you operate within a 100 mile radius of the normal work reporting location regardless if the truck is loaded or not. If you are visiting another location, over 100 miles away, you must use a Log Book. I witnessed this. It happened to a Sales Engineer (he was out of state) and was driving a truck after a sales event. D.O.T wrote a ticket. It cost his employer thousands more to fight it, plus he had to make a court appearance. Don’t get caught!
ABS and tire size
The speed calculation for an exciter ring with 100 teeth is based on a default tire size of 510 revolutions per mile. This figure is based on the actual rolling circumference of the tires, which varies with tire size, tire wear, tire pressure, vehicle loading, etc. The ABS response sensitivity is reduced when the actual rolling circumference is excessive on all wheels. For a 100 tooth exciter ring, the minimum number of tire revolutions per mile is 426, and the maximum is 567. The ECU will set diagnostic trouble codes if the number of revolutions is out of this range. In addition, the size of the steer axle tires compared to the drive axle tires also has to be within the ABS system design. To avoid diagnostic trouble codes, the ratio of the effective rolling circumference of the steer axle, divided by the effective rolling circumference of the drive axle, must be between 0.85 to 1.15. CAUTION: The ESP system effectiveness relies on the accuracy of vehicle speed. If a major change on the tire sizes occurs such that odometer setting needs to be changed, the Advanced ABS controller's setting of tire sizes must be reprogrammed to new values at the same time by a certified mechanic.
Brake lights w/Jake
If your customer does NOT want the brake lights to illuminate during Jake operation (standard with Cummins engines), request they do not light with Jake brake activated.
HAULMAAX was the evolution of HN that brought lower costs and lighter weight. It also brought the “virtual center point” down. HN has the bolsters on top of the beam, HAULMAAX has the bolsters down the side. This was important for high center of gravity vehicles. This made the HAULMAAX much more roll stable than the HN for these applications. The HN also has larger and stiffer bolsters springs where it takes more load to engage the auxiliary spring, or the second stage of the suspension. Because the bolsters are on the top of the beam, they needed to be stiffer for the HN roll stability. This also has a negative impact on ride. In addition, shimming the aux spring is more important on the HN. Hendrickson upgraded the HAULMAAX with the PLS (progressive load spring). This eliminated the need for the maintenance of shimming (you still need to check the shims as they will still wear over time), it eliminated the strike through events. When a truck fly’s over the intersection or crown of the road the suspension will “slap” down (the auxiliary spring striking the shim plates) creating a jarring event. The PLS is engaged at all times (unloaded and loaded). In the unloaded state, it provides a smooth rate curve – meaning a nice spring rate for a comfortable ride. As the truck is loaded, the PLS will compress into the second state providing high roll stability. Because the PLS is always engaged, this also protects the bolster springs because it shares in carrying the load = longer bolster life. Many people don’t change out the auxiliary spring or PLS when below 3 inches in the free state. This leads to all of the load getting carried on the bolsters which leads to premature failures – or short bolster life
Jost 5th wheels
These are designed to be rebuilt on the chassis. Holland and Fontaine are rebuilt from the bottom and must be removed and flipped over. Less than ½ hour to rebuild the Jost vs. at least 2+ for the others.
Chalmers vs. Hendrickson suspensions
Chalmers Suspensions are based on a “FLOATING WALKING BEAM” design, (not tied to the axles), with a Load Guard rubber spring (rubber puck) that allows Chalmers’ System to work as an independent suspension, no transverse torque rods. The rubber spring is controlled via different restrictor cans which can be easily changed depending on ride or stability requirements. The load is equally distributed to each wheel and maintains equal traction on all four dual wheels at all times. Articulation is only limited by the axle stops or vehicle frame max of 16 ½ inches, therefore eliminating frame twist and breaking transverse torque rods.
Wingman Side sensor
This is ONLY allowed at time of build. It CANNOT be added later, so make sure your customers are aware.
CDL log book
Besides the 100 mile radius, there is one other exception. If you have questions, Google Federal Motor Vehicle Safety Administration. In doing research on this, I found there are STATE requirements which can be enforced on drivers, so do your homework. Non-CDL Short-Haul You are not required to fill out a log with a graph grid if you come under the non-CDL short-haul exception. The non-CDL short-haul exception applies on days when you: - Drive a truck that does not require a CDL, - Work within a 150 air-mile radius (see p. 3 for explanation of “air miles”) of your normal work reporting location and return there each day. - Follow the 10-hour off duty and 11-hour driving requirements, - Do not drive after the 14th hour after coming on duty on 5 days of any period of 7 consecutive days, and - Do not drive after the 16th hour after coming on duty on 2 days of any period of 7 consecutive days. Your motor carrier must keep time records of the times you report for and are released from work each day, and the total hours on duty each day.
ILS 5th wheel
ILS 5th wheel is the light weight option. No welding is allowed on this wheel, including modification of adding the Convertible brackets which allows this wheel to be used with frame and frameless end dumps. Holland has a bolt on apparatus: You also have to replace the top plate with one designed for the No-Tilt. In a nut shell, you might consider buying a No-Tilt from the factory on a STOCK day cab tractor to keep from having to modify an existing wheel.
Allison Heavy
When specing a 4500RDS or 4700RDS coupled to an 1850 torque engine for heavy haul, make sure you review the SCAAN (NOT iSCANN) with the customer. Allison allows this higher torque because they cap the engine torque at 1650 in the first group of gears with Low range torque protection or LRTP, so if the loads are such that the transmissions pulls down in the 3 lower holes on the 4500 or 4 lower gears in the 4700, then torque is reduced to 1650, so given that, if they are pulling with manual transmission chassis, yes the Allison will be the last one to the top of the hill.
Federal excise tax is a 12% sales tax imposed on the first retail sale of truck, trailer, and semitrailer chassis and bodies, and tractors (trucks over 33,000 lbs. GVWR, tractors with a GVWR over 19,500 lbs. and have a gross combined weight, in combination with a trailer or semitrailer, of 33,000 lbs. or less and trailers over 26,000 lbs). The funds derived from the FET are deposited in the Highway Trust Fund HTF). If you have any questions see; The SELLER is liable for the tax. Parts or accessories. The tax applies to parts or accessories sold on or in connection with, or with the sale of, a taxable article. For example, if at the time of the sale by the retailer, the part or accessory has been ordered from the retailer, the part or accessory will be considered as sold in connection with the sale of the vehicle. The tax applies in this case whether or not the retailer bills the parts or accessories separately. The taxable articles listed earlier do not apply to an idling reduction device or insulation that has an R value of at least R35 per inch. The tax does not apply if the installed part or accessory is a replacement part or accessory. The tax also does not apply if the total price of the parts and accessories, including installation charges, during the 6-month period is $1,000 or less. However, if the total price is more than $1,000, the tax applies to the cost of all parts and accessories (and installation charges) during that period. Example. You bought a taxable vehicle and placed it in service on April 8. On May 3, you bought and installed parts and accessories at a cost of $850. On July 15, you bought and installed parts and accessories for $300. Tax of $138 (12% of $1,150) applies on July 15. Also, tax will apply to any costs of additional parts and accessories installed on the vehicle before October 8.
CNG/LNG weight
Tanks are heavy and need to be properly located at time or order to achieve the correct 5th wheel or body position. With saddle and cabinet tanks, chances are good you’ll weigh more than 12K on the steer. You will be responsible for weight distribution. Use the Super Tractor Calculator to arrive at the impact on CG.
Make sure you take the size of BOC Cabinets into account when you figure CG and arrive at the correct wheelbase. The Super Tractor Calculator can assist with this.
For saddle/rail (horizontal) tanks make sure to include the difference between the item spec'd under cab from the factory and the actual weight of the gas tank that will be installed aftermarket. You need to accomodate for this difference when calculating the CG.
CNG Usage
Ask the CNG manufacture (Momentum, Agility, Worthington - Trilogy/D-Hybrid, Quantum, etc) about usable fuel to determine range. All manufactures are different. It’s much like diesel tanks. Some OEs use true usage where others define capacity. Subtract 10% to get usable. CNG is no different, except that the usage is much less than what’s advertised. For example, 80-85% fill is common on a 70 degree day. It’s less as ambient temp increases, so filing at the coolest part of the day/night helps. Slow fill is better than fast. Then you have to take into account the unrecoverable fuel at low pressure. The tank manufacture and gas stations, control much of this. It also depends on the number of tanks. Stations sell CNG by GGE (gasoline gallon equivalent), so throw that into the equation Make sure you work with the tank manufacture to determine accurate range expectations and projected fuel economy.
CNG vs. diesel weight
DEF weighs approximately 9 lbs. gal, and Diesel at 7 lbs./gal. Also the weight of the aftertreatment is included in the diesel exhaust weight, so remember to subtract that with gas.
CNG cabinets
Make sure you document the height of the cabinet from the supplier and identify on the sales order. Yes, Green House Gas is the reason for this exercise. One would think CNG/LNG would catch a break from Green House Gas, but it doesn’t.

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Vehicle Speed Limiter (VSL) and Engine Idle Shutdown Timer (EIST) are Emission Controls that may be noted on the door label. The default VSL speed is 64 MPH and EIST requires 5 minute idle shutdown. The expiration distance for these parameters is between for 300,000 - 1,259,000 miles and CANNOT BE RESET during that period. The expiration is not noted anywhere on the vehicle. You must call Parts and get this number, and use an engine tool to remove the value when applicable, if desired.


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