[bicoven]

After 130000km - around 80000 miles - there is a small amount of transmission fluid, which appears to have escaped from the transmission.
The fluid seems to have leaked from the black rubber cover, as opposed to from the joint between the engine and the transmission. Please see the pictures.
Anyone knows what might be the reason for such leak
Thanks for sharing.

[ezaircon4jc]

Originally Posted by bicoven

After 130000km - around 80000 miles - there is a small amount of transmission fluid, which appears to have escaped from the transmission.
The fluid seems to have leaked from the black rubber cover, as opposed to from the joint between the engine and the transmission. Please see the pictures.
Anyone knows what might be the reason for such leak
Thanks for sharing.

Gasket or seal...

[EL Jeffe 5]

what engine does your car have
I recently had my upper and lover oil pan gaskets replaced
2013 550i
make sure you verify its transmission fluid and not engine oil

[bicoven]

Originally Posted by EL Jeffe 5

what engine does your car have
I recently had my upper and lover oil pan gaskets replaced
2013 550i
make sure you verify its transmission fluid and not engine oil

Originally Posted by EL Jeffe 5

what engine does your car have
I recently had my upper and lover oil pan gaskets replaced
2013 550i
make sure you verify its transmission fluid and not engine oil

The engine is N57D from 2013

Very good point Thanks.

It could have been engine oil...It was difficult to tell, because it's been around there a while and gathered some grit and soot.

Cleaned up the area, and will revisit in 5-6k km for a follow up on that leak. Maybe it will show clearly then...

[ezaircon4jc]

Originally Posted by bicoven

The engine is N57D from 2013

Very good point Thanks.

It could have been engine oil...It was difficult to tell, because it's been around there a while and gathered some grit and soot.

Cleaned up the area, and will revisit in 5-6k km for a follow up on that leak. Maybe it will show clearly then...

Give it the smell test. Trans fluid and engine oil have distinctly different smells.

[Bav@Heart]

Interesting, I noticed the same thing on my 8HP45, but it was super sticky, almost like gum. I am guessing it was on there for a while. If I find the culprit, I will be sure to report back.

[Boosted M5]

That my friend looks just like mine, I don't believe it's transmission fluid, I suspect based on the mileage that it's either an upper oil pan gasket leak or worse coming from the oil return cover for the turbos.

[Bav@Heart]

I have the same leak. Cleaned it up a few thousand miles ago and it is there again. Anyone figure it out?

[badblack550xi]

did you check rear main seals ?

[bicoven]

Originally Posted by bicoven

The engine is N57D from 2013

Very good point Thanks.

It could have been engine oil...It was difficult to tell, because it's been around there a while and gathered some grit and soot.

Cleaned up the area, and will revisit in 5-6k km for a follow up on that leak. Maybe it will show clearly then...

Originally Posted by bicoven

The engine is N57D from 2013

Very good point Thanks.

It could have been engine oil...It was difficult to tell, because it's been around there a while and gathered some grit and soot.

Cleaned up the area, and will revisit in 5-6k km for a follow up on that leak. Maybe it will show clearly then...

So continued...

After approximately 11000 km I checked again the transmission case around that area for leaking. This time leak trace is barely detectable, just slightly "oily" feel to the touch, but not an amount that will show up on a picture. Could as well be a residual after the cleaning previous time. As a result not sure what to think - is there a problem or not :

Note in the original photo there is some visible damage to the soundproofing material on the sump. It was stuck on the metal there, and it was soaked in oil.

Although not seen in the photo, just next to this area there is the oil sump drain. Could it have been engine oil, that soaked the soundproofing around the drain during previous oil changes, and then ran off further back where I noticed it?

Thanks for sharing your speculations/ thoughts on that.

[jimk]

I'm fairly certain that the ZF 8HP fluid has a uv dye in it so you can use a uv flashlight to trace the leak.

[Black_Banana]

Hi im new on these forums but I follow the threads and I'd like to resurrect this one. I'm having the same leak and same amount of fluid. Did op ever find the root cause?