final drive ratio 1.0 corvette issues changing gear ratio

[v8vegaman]

I seem to having some issues with changing the gear ratio on a ECM and TCM, it seems that the final drive ration stays 1.0 even when I change the gear to 3.50, and of course it shifts way too early and is driving me nuts. Is there a reason that the final ratio doesn't seem to change from 1.0? H0103. Even when I uncheck the box marked (Transaxle: Corvette or front wheel drive).

40 pulse on the output speed sensor (H0102)

This is from a 2006 Corvette LS2 and using a T42 and a 4L60E. The T42 has the programming for the 4L60E and the corvette vin is on both the ECM and TCM

This is an engine swap into an older vehicle with the LS2 and 4L60E bolted directly to the engine and then through a rear diff with 3.50 Gear. Tire is 235-70-15

ECM 12603892 service number Calz. 12605732

[Taz]

Hello Robert,

To me, it has always seemed to be a quirk in the software. When working with a Corvette tune in a Hot Rod, I just change the VIN (to a truck or some other RWD vehicle) on the "home" screen in the V7.5 Tune Tool, then save the tune, and close the software. When you reopen the tune, as long as the modified VIN appears, you should be able to make permanent changes to the Speedometer segment.

The VIN is not rewritten when you flash the tune - so no issue there. Also, you don't need to change the actual VINs in either controller (you can if you want).

Cheers,
Taz