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GEARING GUIDANCE

Engine

Heavy-Duty engine, sufficient for GVW/GCW =< 85,000 lbs.

Operation Profile

Application of vehicles which spend 90+ percent of time at highway speeds on paved surfaces

Operation Profile

Transmission is manual with a clutch. Driver selects appropriate gear for current road conditions. Typically 10 - 18 speeds

Transmission Gearing 

10B

Constraints Messages- click on constraint to address issue 

* Change Drive Axle Ratio

* Consider automated or automatic transmission to remove driver variation & get maximum economy

* Gearing is not for an automatic transmission. Choose Allison 5-7 Speed or TC10

Engine Speed Calculator

Miles Per Hour

Miles Per Hour:Speed at which the vehicle will operate the majority of use

Tire size: Revolution/Mile - Review drop to see basic tire size rev data

Ratio, Drive Axle : Enter a smaller number (faster ratio) to decrease RPM or a larger number (slower ratio) to increase RPM, as necessary

Drive Axle (RAX) Ratio

Top Gearing Ratio

Ratio, Transmission Top Gear: Derived from the Transmission Gearing input selection above

Ratio, Auxiliary Transmission: Review drop to see basic ratios. If not using an auxiliary use the N/A value of 1.00

Calculated RPM falls within range for the Operation Profile specified

Debugging

Calculated RPM falls within range for the Operation Profile specified

 Gearing Assessment

Engine RPM Range

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