Allison code list, tq. specs, and other info

[race691]

does anyone know which solenoid controls shift between 1st & 2nd gear. My 01 is slamming into 1st on downshift.

[More Power]

As I recall, the Allison can be manually controlled using a Tech II scan tool. A GM tech can go on a ride-along, and select different gears as a way to test the transmission systems. Might be worth a shot.

Secondarily, the Allison has always been a "smart" transmission. The programming learns from the way thee truck is being used to modify its shift scheduling. There are ways to reset the learning process, and have the transmission begin the process again. A search here in this forum for the appropriate keywords should produce more reading and instruction. Jim

[race691]

I actually changed the whole valve body today and it is much worse now than my original problem. I am putting the old valve body back in. When l come to a stop it almost feels as if the truck wants to creep forward