GM 6L80 Transmission Information Thread

[CTX-SLPR]

From Sonnax:

That ball being missing very well could have played a factor in your symptoms. It is in the 1st gear circuit and was added to fix downshift complaints and engagement issues.

Those are pretty much my exact complaints so that's a good sign that I'm on the right track.

 

[CTX-SLPR]

So far so good, other than a brief scare when I hit the Trans Fast Learn button in HPTuners and I lost all gears things seem really good. I restored operation by just reflashing the TCU with the tune and the test drive was totally normal. Only thing I noticed was it felt a little soft going into top gear accelerating away from a light a moderate throttle but I don’t really remember how that was before.

Tomorrow I’ll go for a much longer drive to get the temp up to at least the 180’s and see if the 1st gear “overrun” on decel or delayed engagement pulling away come back.