Problem With Oil Leaking Between The Trans And Engine?

BimmerDude · #1 03-02-2007, 01:37 AM

Hello everyone! I have this small leak of oil coming from the trans and engine. I took it to the dealer and they said it was the "Rear main seal".
So they changed it under warranty. But a few days later I got the same F$&*#* leak again!!!

So I took it back today. Now they still haven't found the problem yet, they said its such a small leak that its not very noticeable, plus it is on the back of engine all the way on they top side. So what they have done is put this oil dye in the engine to see tomorrow with a black light as to where the oil is leaking from. Does anybody know what this could be? And if so what can be done? Thanks. Everyone on this site is 150 Times smarter then those so called techs that BMW has.

Zulu95 · #2 03-02-2007, 09:15 AM

Which engine?

Sterling · #3 03-02-2007, 10:03 AM

hopefully its not a headgasket.... could be a valve cover gasket and numerous other possibles

vinuneuro · #4 03-02-2007, 11:21 AM

Dude, get away from Patrick. Between them and Knauz, they couldn't combine to produce one competent service department. If it wasn't the rear main seal, it might either be a cam seal or headgasket. A simple leak down test would easily allow them to rule the headgasket, or not.

fast4d · #5 03-02-2007, 12:16 PM

Quote:

Originally Posted by BimmerDude

Hello everyone! I have this small leak of oil coming from the trans and engine. I took it to the dealer and they said it was the "Rear main seal".
So they changed it under warranty. But a few days later I got the same F$&*#* leak again!!!

So I took it back today. Now they still haven't found the problem yet, they said its such a small leak that its not very noticeable, plus it is on the back of engine all the way on they top side. So what they have done is put this oil dye in the engine to see tomorrow with a black light as to where the oil is leaking from. Does anybody know what this could be? And if so what can be done? Thanks. Everyone on this site is 150 Times smarter then those so called techs that BMW has.

make sure it's transmission fluid. if it's not then it's the valley pan gasket and coolant is leaking. it runs down the back and drips from the bell housing.

noncom23 · #6 03-02-2007, 12:28 PM

Sure its not the front seal?

vinuneuro · #7 03-02-2007, 01:21 PM

Quote:

Originally Posted by noncom23

Sure its not the front seal?

Trans side= rear portion of the engine LOL.

noncom23 · #8 03-02-2007, 04:28 PM

I thought front seal is between engine and tranny. Rear seal, tranny and drive train. If that is true, whats so funny?

Quote:

Originally Posted by vinuneuro

Trans side= rear portion of the engine LOL.

JCL · #9 03-02-2007, 04:47 PM

Quote:

Originally Posted by noncom23

I thought front seal is between engine and tranny. Rear seal, tranny and drive train. If that is true, whats so funny?

Vin thought that you meant the front seal of the engine. You were talking front seal of the transmission. Quite logical IMO.

JCL · #10 03-02-2007, 04:57 PM

Bimmerdude:

I think you should relax. They may or may not have got the rear seal wrong. You don't know yet. Whatever it actually is, they are far more likely to be able to determine it than we can on this board. You have a warranty. What is all the drama?

The rear seal was the original diagnosis. It may have been leaking and been diagnosed correctly, but it may not have been the only leak. Also, it might still be leaking, depending on the condition of the crank where it contacts the seal, and the quality of the repair. Or, maybe it was never the problem. You are assuming the latter, but that is not necessarily a safe assumption.

If it is showing higher up, it could be thrown there, or it could be leaking there. If it has been leaking for a while, the area will all be oily and it won't be obvious where it is coming from. Using the dye sounds very logical to me, not sure why you wouldn't want to know for sure prior to randomly replacing seals and gaskets. Let them do it.

If many parts have been replaced, and there is a leak, it is more likely that it is a leak from prior workmanship than a part defect IMO. We can tell you what parts are likely to leak (oil breather, cam seals, etc) but not about the work that was done previously since we just don't know.

You say it is oil, but many posters here are questioning whether it really is, since other fluids can pick up oil as they drip down and often appear to be oil. We just want to be sure, and I don't know how you know for sure it is oil.

I would suspect the head gasket, or valve cover gaskets. You can't test for either, you have to find out where it is leaking. There is also the possibility that there is enough oil around the rear of the engine that you are seeing residual drips, and not a continuing leak. I don't know how long it has gone on for but that is a possibility.

My final advice is to let the mechanic do the search. If you don't trust them at all, then simply take your vehicle away, that is your choice. You do risk creating liability in that case, however, if one mechanic left something undone and another shop finds it. Who pays? Likely you unless/until they accept responsibility.

Good luck

Jeff