Allison 5sp: Looking For Input

[RobsDmax]

Was sled pulling this weekend 3rd gear 4 low, got to the end of the pull and went to shift into neutral to prevent turbo bark. Shifter went right to reverse, I saw it shifted back to neutral then got a cel and pulled codes of p0700 p0746 and p0843. As far as I can tell it was a limp and it had to do with solenoid a sticking. Is the solenoid gone and in need of replacement? Fluid levels seem fine and I cleared codes and drove 30 km home without problem? What do you think Mike or anyone else

 

[RobsDmax]

bump this up, wanna see what mike or someone knowledgeable in allisons has to say, ive driven truck since i cleared codes at least 80 km seems to shift through all 5 fine and lock t/c even on my 90 hp tune, i was watching pulling video seemed to downshift and drop all boost, wondering if i was way over speed with track conditions

 

[RobsDmax]

bump it up, wondering how bad it was hurt limping in third 4 low

 

[JoshH]

You didn't have a slip code.

 

[RobsDmax]

You didn't have a slip code.

as far as i can google, the codes were all in relation to solenoid a, would that be my problem??

 

[MACKIN]

Can't tell what your looking for here. Seems to me when you shifted the truck at the end of the pull you bumped reverse while moving forward and it threw some codes. Is that the drift of it? Seems like you say everything is fine now?

 

[RobsDmax]

Can't tell what your looking for here. Seems to me when you shifted the truck at the end of the pull you bumped reverse while moving forward and it threw some codes. Is that the drift of it? Seems like you say everything is fine now?

you have that right, im just seeing if it was the shifting that caused the codes, yes everything seems fine now i towed a trailer yesterday on my light tow tune and it seemed fine. drove to school on my 90 same thing seems fine

 

[Mike L.]

Well P0746 would indicate that an on coming clutch controlled by Trim sol. A came on too slow. You were steady state ( locked in gear ). You indicate that you were in 3rd which is not controlled by Sol A and neither is reverse. Could you have fooled the TCM by quickly shoving the shifter into reverse? Maybe. 3rd gear had sol. C and F activated. When you shove the shift lever into rev, TCM might have seen shift valve C destroke when it should have been stroked and pressure switch lose ground ( P0843 ) and assume loss of pressure in the valve body.

 

[MACKIN]

Well P0746 would indicate that an on coming clutch controlled by Trim sol. A came on too slow. You were steady state ( locked in gear ). You indicate that you were in 3rd which is not controlled by Sol A and neither is reverse. Could you have fooled the TCM by quickly shoving the shifter into reverse? Maybe. 3rd gear had sol. C and F activated. When you shove the shift lever into rev, TCM might have seen shift valve C destroke when it should have been stroked and pressure switch lose ground ( P0843 ) and assume loss of pressure in the valve body.

Which means if it aint broke don't fix it! Take two shots of DexIII and if it does break give me a call between 7 and 5 PST! :roflmao:

 

[RobsDmax]

Well P0746 would indicate that an on coming clutch controlled by Trim sol. A came on too slow. You were steady state ( locked in gear ). You indicate that you were in 3rd which is not controlled by Sol A and neither is reverse. Could you have fooled the TCM by quickly shoving the shifter into reverse? Maybe. 3rd gear had sol. C and F activated. When you shove the shift lever into rev, TCM might have seen shift valve C destroke when it should have been stroked and pressure switch lose ground ( P0843 ) and assume loss of pressure in the valve body.

thanks mike i was just looking to see what you thought, i have really no idea besides the fact that it most definitely was in limp mode. changing the fluid probably wont make any difference?? i have some transsyd sitting on the shelf anyway

 

[RobsDmax]

Which means if it aint broke don't fix it! Take two shots of DexIII and if it does break give me a call between 7 and 5 PST! :roflmao:[/QUOTE

thanks i think....

 

[Mike L.]

I doubt changing the fluid would do anything.

 

[RobsDmax]

alright, thanks

 

[RobsDmax]

I doubt changing the fluid would do anything.

would you drop the pan to look for clutch material? and or broken wires?

 

[Mike L.]

No. If wire was broken it would code and Alli would not work. Back off and drive it for a while and see what happens. You did some crazy shit and I think the TCM did also.

 

[RobsDmax]

No. If wire was broken it would code and Alli would not work. Back off and drive it for a while and see what happens. You did some crazy shit and I think the TCM did also.

alright thanks mike