allison problems P0757

[jmar243]

can anybody help me out?
these 2 codes come up
P0700 tells the engine transmission is malfunctioning
P0757 soleniod b is stuck on
the computer notices this because there is excess pressure but the soleniod might not be stuck open

i ran the truck hard then drove about 3 miles and let it idle for 10 min and shut it off, is started it up and drove it out the lane and shifted into 3 and the rear tires completely locked up, went back and then went front, kept on going out the driveway, i was coasting down a hill and it was like i put the brakes on then the truck stoped and would not go anymore rev the engine some and it would not go at all but would go in reverse, it was like a valve was slowly leaking pressure into another gear or something

i pulled the valve body off and looked for stuck valves or dirt or anything, everything appears to be ok but i am also not experienced with transmissions
oil looks ok a little dark but not bad
small pieces of clutch material in oil pan but this could be normal to i am not sure

any help would be greatly appreciated:hug:

 

[Mike L.]

Don't think it's going to be simple if you see clutch material in the pan. Cut the filters open and see what's inside. Could be a short but I doubt it. Maybe a bad pressure switch manifold which is cheap and easy to replace.
I'm betting a valve stuck because of clutch material.

 

[TrentNell]

Don't think it's going to be simple if you see clutch material in the pan. Cut the filters open and see what's inside. Could be a short but I doubt it. Maybe a bad pressure switch manifold which is cheap and easy to replace.
I'm betting a valve stuck because of clutch material.

X2 last time I saw that code and had reverse and no forward gears , the C-1 's were the culprit , but as Mike said drop the pan , cut the filters open and check for clutch material .

 

[jmar243]

thanks for the advice
i was just not exactly sure what was going on
Thanks again:thumb::thumb::thumb:

 

[JoshH]

What does it do if you put the truck in neutral?

 

[jmar243]

What does it do if you put the truck in neutral?

when i put it in neutral it goes into neutral
when i put it into d it does not go but when i put it into r it does go into reverse

So i cleaned the valve body and put it back in
now i can drive it without it locking up the rear tires

when i put it in D it engages hard
R engages har
but the second gear shift there is a big defuel and then it slams second
3rd is normal
4th is a little more aggressive than normal but not bad
5th is good
6th is good
when it goes to lock tc if i am hard on the throttle it locks properly, but if i am going lets say 51.1,51.2,51.3 etc. anotherwords very light on throttle it engages dissengages engages it is like it is not sure if it should lock or not

any suggestions on how to fix this would be greatly appreciated Thanks

 

[MACKIN]

It's toast. If it's locking up the rear wheels then the clutches are hung up as the steels are warped and there is no clearance.

Order your parts or find a builder

 

[jmar243]

It's toast. If it's locking up the rear wheels then the clutches are hung up as the steels are warped and there is no clearance.

Order your parts or find a builder

it does not lock up the rear wheels anymore though since i cleaned the valve body

 

[JoshH]

Sounds like you have some problems. I would be pulling the trans and checking clutch packs. The activity shown in your avatar isn't helping your trans any.

 

[jmar243]

Sounds like you have some problems. I would be pulling the trans and checking clutch packs. The activity shown in your avatar isn't helping your trans any.

the truck was hooked to a sled 11 times this summer, and did about 5 drag runs
does that make it time for a refresh?

 

[JoshH]

No, but your problems make it time to at least look at it. Something is definitely not right.

 

[SteveFord]

This isnt a stock trans with the mods listed in the sig is it??

 

[jmar243]

This isnt a stock trans with the mods listed in the sig is it??

no it has a suncoast kit with a 1058 converter and c3 oiler

 

[mack attack]

Hey Jmar243 I am having the exact same problem. When the truck shifts into 2nd the rear tires lock right up. and when its on the lift it looks like the accually start turning backwards!!! I just rebuilt trans and put it together so all the clutches and frictions are good with good clearance. Did you find your problem??

 

[jmar243]

Hey Jmar243 I am having the exact same problem. When the truck shifts into 2nd the rear tires lock right up. and when its on the lift it looks like the accually start turning backwards!!! I just rebuilt trans and put it together so all the clutches and frictions are good with good clearance. Did you find your problem??

sorry for the late reply lol

there was a lot of dirt in the pan, c3 clutches needed replaced and the valves were hanging up, also the torque converter was on its way out, clutch material was pouring out of there as well