Hey Guys. We are working with a unique project and would like to resolve our speedometer issues. The vehicle is a 2007 Tahoe LTZ SUV with a GM LS7 7.0L engine and GM 4L80E transmission.
First of all, see our most recent attached tune file...
We have had the OEM 07 Tahoe PCM & TCM flashed with a new VIN for a vehicle with a 4L80E transmission, for proper operation.
Our issue is that the speedometer is off because of a gear change size. We attempted to use the automatic calculator by typing in the tire size and gear ratio, but they are not clickable and are shaded out. Why is this happening? Our speedometer is clearly off calibration...
I appreciate everyone's help... Please advise.