Originally Posted by
DickForster
2018 Silverado 5.3L, rebuilt 6L80 with new Precision HD (billet case) torque converter. I have watched lots of youtube videos and reading and went with this approach - no TCC in 1 through 3, 0 slip TCC in 4 through 6. Increase the lock pressure. Also used bearcat to make shift rpm adjustments, but I don't think that speaks to the TCC performance that I am seeing.
Regulator offset is set to 90 psi, gain 1.0. All slips are set to 0. Apply Ramp table set to 300 above 0 slip error, Max Pressure 200 psi.
In the scan, when the truck first shifts to gear 6, a few seconds later the TCC locks, the desired slip goes to 4.5 rpm??? That is nowhere in the tune that I can see, should be 0.
The line pressure there is around 45 psi. Where is the 90 psi offset?
Anyway, the speed is varying a bit as I am in traffic. When the line pressure goes to 600 psi, that's where I used the Scanner override to force TCC Lock. TCC slip goes down but is not a hard 0, small wiggles. Then I enable cruise at 65mph. Then I set TCC Lock to Off and the line pressure goes to 0. Then I disable the TCC Off and the line pressure goes to a stable 110 psi, yay, but eventually it drifts downwards to 70 psi or so. This doesn't seem to match how I would predict it to behave from the tune.
Could use some expert advice here. Thanks.