90TR

Hi, I completed a 5.3 swap into a Hummer H1 that was originally a Gasser 5.7 SC. The 5.7 was smoking like crazy, but the tranny was never an issue. The 5.3 is running well but the tranny is now acting up. I am controlling the tranny from the 2004 5.3 Yukon computer using HP Tuners. I have loaded just about every program available, but the problem remains. After running at highway speeds for a few minutes the Force Line Pressure pegs at 90 and will not drop until I shut it down for some time. I have replaced all the sensors twice- Solenoid A, Solenoid B, EPC Pressure Control Solenoid, TCC Lockup Solenoid, and harness, manifold pressure switch and filter. I don't understand why it pegs and won't release after being on the highway. Another note is that the 1-2 shift is harsh, and I cannot seem to get it anywhere near as smooth as the 2-3 or 3-4 shifts. IT was never all that great, but it is worse.


Thanks for sharing your experience, Bill