E53 3.0 diesel no reverse, drives forward in neutral

[Redraptor141]

If it’s like the ZF transmissions, these harden up and can cause hard shifting. But they could definitely cause slipping, as if the leak causes a PX drop it would reduce the clamping pressure. But this is a theory but a valid one. And cheap (on the ZF boxes)

For the price of them it would be worth changing them. Equally I’d change all of them
As a set as they are rubber parts so if ones shot all might be on there way out. If they are the same as the ZF boxes then they are easy to change, drop the mecatronics, and just some needle nose pliers and twist and pull.

Obviously again I’ve only been inside a ZF box but I think the component does the same in the GM one

[samuelis01]

Okay, so here is another update.

I have dropped the pan and pulled the valvebody off. I have checked that rubber seal that I have circled in the previous post and it is not it, Rubbber is soft, does not seem deformed in any way. I have also compared it with another one I had from the other transmission and they were identical.

So I have decided to try to slap on the valvebody that i havent messed with from the junkyard transmission that I have mentioned couple times earlier to see if something changes.

And something did indeed change. Now I am not only getting ganguberwachnung 5 , I am also getting ganguberwachnung 3 error.. and it shifts like complete garbage.. 4th gear comes with a bang and shift to 5th seems really delayed so not too much luck today.

Thats it Im buying new valvebody. I think that it is the root of my problems and also caused forward clutch to burn. Valves themselves are not worn but bores are quite loose.

[RRPhil]

Just wondered if you checked the overdrive clutch (4-5 shift) accumulator when you had the transmission apart?



Phil

[samuelis01]

Yes, I have checked the accumulators.
Only worry I have about accumulators are the springs. Manual that you have pulled drawing of the transmission from states that all 4 are identical. But this is obviously incorrect. It is possible that I have mixed them up. I am pretty sure that this can cause harsh shifting but can it cause limp mode and trouble codes?
Before i have disassebled transmission first time 3 out of 4 springs were broken into small pieces and it was still driving forward fine without jerking or limp mode.
Do you know of any documentation that states which spring goes into which accumulator please?

EDIT :
So i have found a document regarding springs. But it does not really match with my situation.
All of my springs were plain with no color marking.
Set that I am running now and before is from that junkyard transmission. But a havent kept them in order. They are all plain too and they have light differences in length (i thought that this is an deformation due to age and wear) I have put them in randomly both times. Could this really be the source of my problems? I just really can not see how this would cause those trouble codes.

[samuelis01]

Ok so I am happy to say that my gm transmission is fixed. I have been driving it for couple past weeks and no more limp mode.

Position of accumulator springs is apparently crucial for proper function of gearbox. If you get springs mixed up just like me, good rule of thumb that shortest spring goes into direct clutch accumulator this accumulator is also bigger diameter than other three in X5.

One from three remaining springs is much weaker and is made from thinner wire. This is also sometimes painted orenge and goes into 4-5 accumulator.

Last two springs might either be same or one of them can be longer by couple milimeters. If thats the case then the longer one goes into 1-2 shift accumulator.

Not putting the softest orange spring into 4-5 accumulator will cause 4-5 clutch slipping and damage. I have learned this the hard way but it that I have caught it in time as it seems to drive fine now 😀
Thx guys for help, car is working, repair cost me basically norhing and i have learned a lot about old automatic transmissiions.. Great success 😀

[Falkon]

Originally Posted by samuelis01

Ok so I am happy to say that my gm transmission is fixed. I have been driving it for couple past weeks and no more limp mode.

Position of accumulator springs is apparently crucial for proper function of gearbox. If you get springs mixed up just like me, good rule of thumb that shortest spring goes into direct clutch accumulator this accumulator is also bigger diameter than other three in X5.

One from three remaining springs is much weaker and is made from thinner wire. This is also sometimes painted orenge and goes into 4-5 accumulator.

Last two springs might either be same or one of them can be longer by couple milimeters. If thats the case then the longer one goes into 1-2 shift accumulator.

Not putting the softest orange spring into 4-5 accumulator will cause 4-5 clutch slipping and damage. I have learned this the hard way but it that I have caught it in time as it seems to drive fine now 😀
Thx guys for help, car is working, repair cost me basically norhing and i have learned a lot about old automatic transmissiions.. Great success 😀

Congratulations!!!!!!!! Great job. I applaud your perseverance.

[RRPhil]

That's great news

Phil