Allison 5sp: slipping issures

[djms]

Hey guys I got my truck back yesterday everything was great, I put about 150 miles on and today I got on it from a dead and when it shifted into second gear made kind of a popping sound, I knew something wan't right anyway. Now the lower gears slip really bad I don't know about 4th and 5th because Im not trying to let it slip. When I say slip bad I mean it takes me about a mile to get to 35 mph if I give it more than like 10% throttle the rpms go up but the truck dont move. Any Ideas?? After the converter locks up and I try to push it just a little more so I can get going it unlocks as well, it is a Ml converter with about 5k miles. Thoughts?

 

[TrentNell]

hey guys i got my truck back yesterday everything was great, i put about 150 miles on and today i got on it from a dead and when it shifted into second gear made kind of a popping sound, i knew something wan't right anyway. Now the lower gears slip really bad i don't know about 4th and 5th because im not trying to let it slip. When i say slip bad i mean it takes me about a mile to get to 35 mph if i give it more than like 10% throttle the rpms go up but the truck dont move. Any ideas?? After the converter locks up and i try to push it just a little more so i can get going it unlocks as well, it is a ml converter with about 5k miles. Thoughts?

codes ? Builder ?

 

[Mike L.]

Sounds like an E shift valve hung up. DO NOT DRIVE IT> Get codes and post them.

 

[djms]

p0776 and of course 0700

 

[TrentNell]

I would contact the builder , p0776 usually happens from clutch material holding the valve up , could be a simple stuck valve but pan needs to be dropped and the valve body inspected and if clutch material is seen then she is done , and needs to be pulled .

 

[djms]

Well it was built about two years ago. What valve is it that is stuck?

 

[djms]

Does anyone know which one 0776 is?

 

[TrentNell]

Well it was built about two years ago. What valve is it that is stuck?

Like Mike said , check the "E" valve , or easy reference is, its the one closest to the trim valves or it is the middle valve

 

[djms]

I seen something like shift valve b stuck open. Where is b?

 

[Mike L.]

Sounds like your trans is done. There is no valve or quick fix for P0776.

 

[djms]

what is need to fix it? Just new clutches?

 

[WolfLMM]

Sounds like your trans is done. There is no valve or quick fix for P0776.

I always thought that was the code that usually pops up when you bust apart the rotating assembly???

 

[WolfLMM]

OT Mike I'm going to call you tomorrow. Got to talk about a 47re

 

[djms]

what is the rotating assembly? Is it expensive?

 

[djms]

Ok my efi says pressure control solenoid b stuck off.

 

[TrentNell]

Ok my efi says pressure control solenoid b stuck off.

Either way , the valve body has to come out and see whats going on . Report back what you find .

 

[RPM Motorsports]

This might help if your doing it on your own. If you just got your truck back, what did they do?