iSCAAN, therefore I am…
- Z-factor Consultation
- Dec 12, 2020
- 2 min read
What is all the talk about an Allison SCAAN?
Isn’t this something the truck OE takes care of?

A SCAAN is a full analysis of the projected vehicle operation. It is needed to verify that the correct torque converter is selected, and that the vehicle will be geared correctly for the application. You can have a conversation with you local Allison transmission representative about the vehicle operation and/or you can rely on the OE Engineering group to run the SCAAN. It is required and conducted in some fashion by Engineering, on every vehicle with an automatic transmission.
So, since Engineering will take care of this, why would you care to duplicate the effort? We encounter this question all the time. Truly, Engineering will not permit a vehicle to be built that is an outlier for performance. But recall how you communicate with Engineering… typically using sales codes. Among OEs there is no master list of sales codes. So, someone is left to map the codes onto the answers that the Allison SCAAN uses to determine best fit. No master mapping table exists. And actually, this is not one someone, it is many different people, making this mapping process a bit subjective. Fact is, even if the Engineer looks at the historical data, with EPA17 (and beyond) engine changes, is the historical data relevant to your chassis?
When it comes to rear axle ratios, several will fall within the guideline, and Engineering will accept all of those. But which will be the closest match for customer expectations. And how closely does the coded sales order match the actual operation?
The value of the Allison representative is a conversation about how the customer operates the vehicle and what the expectations are. The rep may also have called on the customer, be familiar with the operating profile, and bring more to the table than a set of sales codes can.
Beyond this, if the vehicle as built comes into question, your customer will most likely go back to Allison. Having a file on the documents ‘WHY’, goes a long way towards a solution. Do yourself a favor, get involved. Help guide the Engineering of the chassis to eliminate potential customer dissatisfaction. It is so much easier to keep an existing customer than to keep looking for new ones.
Comments