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View Full Version : How to tell when Transmission is gone?



kelhami
05-06-2008, 08:39 AM
Took my 94 530iT (automatic) into mechanic's shop... wanted to have them check Tranny fluid/refill, etc... and diagnose some other issues...

They said they refilled a PINT and that was all it needed (surprising since Ive had a small leak for quite a while). I didnt see anything myself but mechanic claimed fluid was burnt/black. Said, tranny is gone, I need a rebuild.

I asked whether he'd dropped the pan, he said no. I was surprised that such an expensive repair issue was so easily diagnosed! He also said, "your trans program is good" (Doesnt he need to do an electrical diagnostic to determine that?)

Driving symptoms:

Tranny seems to be slipping, but I talked to Kurt and he said it could be some other issues as well, not just blown tranny. Maybe electrical... comps not communicating correctly, etc.

When driving, goes into reverse with a hard engagement, jerks a bit and drives. But in DRIVE, it just revs up and wont go... occasionally it catches and will go forward, but it always rumbles and slips. This gradually got worse, to the point where I just towed it to the shop, rather than drive it. When it was still moving forward it didnt seem to shift gears (rpm didnt drop down a bit and move back up with each gear change) it just keot revving up the whole time.

Tow guy said, sounds like low tranny fluid like fluid is sloshing around in there and when it sloshes in right direction tranny catches, when it doesnt it slips.

Also, tends to pick up when going down hill and catch gear. Up hill itll roll backwards and usually wont catch for a while if at all.

Electrical system isnt working, but before it went out had trans program message fo a while. Some time ago my husband said he and a mechanic friend (non-bmw) changed the fluid... dont know if they added correct fluid or what? Could that create problem?

I am having an electrical diagnostic done, but they said it'd be several hours cause they have to do a long read... had bettery checked, needed a charge, but it was good, as was alternator and starter.

1. I want to know, are these symptoms + dark fluid enough to diagnose Blown tranny?

2. Thats an expensive job ($1850... is that a fair price?) Im in California.. what is a fair price?

3. What else should I have ruled out before I go forward with a tranny rebuild?

4. What questions do I need to be asking these guys?

5. How could guy say Trans Program is "good"? How is that determined?

Thanks a bunch guys... I really wanna rule out everything before I do this rebuild because it may not be worth it.

Ross
05-06-2008, 08:53 AM
It may have once been other issues but continuing to drive it while slipping, rumbling and jerking has almost certainly ruined the clutches. The fluid is black because it contains the burned remains of those clutches.
The mode of failure is academic at this point. You continued to drive a sick trans now it is in need of a complete overhaul.

shogun
05-06-2008, 09:02 AM
Agree, you ruined the tranny by continuing to drive a sick tranny.
Dark fluid and burnt smell = it is dead. Needs complete reman/overhaul.
I am not a specialist, but I have reman quite some of these ZF trannies meanwhile, see pics on my website. So I am talking out of a bit of experience.
My opinion, of course I could be wrong.