8L90 Harsh 1-2 Shift Fix?

[ChevyChase]

I agree with remote starting to get the fluid moving to avoid the first 1-2 shift bang for the day. However, when remote starting my 8L90 after getting in and putting the key in the vehicle jerks forward, while in park? haha i think id rather force the 1-2 air purge shift than feel a bump in park?

I've heard lots of tuners can adjust the TCM to help with the harsh downshifts, anyone had much luck with this or even upshifting?

[1badc10]

Not sure why yours jerks in Park position. I would not think that is a software / configuration issue. I?ve been making adjustments with several things relating to shift scheduling, timing, inertia, etc. My Yukon has over 192k miles on the original 8L90, and I?ve put over 130k miles since starting my own improvement efforts. The 8L90 performs nearly perfect now, but there?s still a few areas when ?coasting? that I need to data log.

[bsiv]

Not sure why yours jerks in Park position. I would not think that is a software / configuration issue. I?ve been making adjustments with several things relating to shift scheduling, timing, inertia, etc. My Yukon has over 192k miles on the original 8L90, and I?ve put over 130k miles since starting my own improvement efforts. The 8L90 performs nearly perfect now, but there?s still a few areas when ?coasting? that I need to data log.

can you elaborate on what parameters you were logging ? im working through some similar issues on a swap with an 8l90 ..thanks