Originally Posted by
IARLLC
So this TCM could be from a 2.0T Camaro, or a 3.6 anything, 5.3 Tahoe, etc. Good thing it set codes. There is no way that it would have commanded enough pressure to handle your LT4.
Within the programming of a T87 are 6 different GM programs with actual part numbers that have to be correct for your application. Each has its own function. When we adjust the calibration via HPTuners I think that we only touch one of those. There are differences between all platforms. If I remember correctly the Corvette TCM program takes direct input from the paddles while all other GMs send tap/up/down via BCM...thus the delays we don't like when manually shifting all of the others. When I installed a T87 in place of a T87A I was working on Yukons, Silverados, and Sierras with the same L86, 8L90E, A4WD NQH t-case, 3.23 gears, etc, etc.