Did the test truck have a t87?
Type: Posts; User: Nathan Turner; Keyword(s):
Did the test truck have a t87?
He did, and when he tested the line pressure after the install it was still at factory setting. Almost like the tcm noticed the high pressure and opened the solenoid.
I have a 2015.5 lml, started having the same issue with it. Iv done quite a bit of research with Allison and GM.It has a T87 tcm witch Chevrolet decided to take over the electronics side of Allison...