[JingChai]

Yesterday I went underneath my 2011 E90 328 6MT to check for leaks and discovered a very slight oil leak on the rear shaft seal (Part #11 here: https://www.realoem.com/bmw/enUS/sho...diagId=23_1032)

I have 79k miles on the transmission and I saw some old oil residue on the bottom of the transmission as well.

For those of you with the ZF S6-17BG transmissions, is it normal to experience a slight oil leak over time? Will I eventually need to replace the shaft seal?

[Efthreeoh]

I'd clean it off first. I thought the same on my car, but it turned out it was the shift shaft seal. So clean both areas of the rear of the trans and keep an eye on it to determine which seal is actually leaking.

[Efthreeoh]

I'd clean it off first. I thought the same on my car, but it turned out it was the shift shaft seal (item 10). So clean both areas of the rear of the trans and keep an eye on it to determine which seal is actually leaking.

[feuer]

Originally Posted by Efthreeoh

I'd clean it off first. I thought the same on my car, but it turned out it was the shift shaft seal (item 10). So clean both areas of the rear of the trans and keep an eye on it to determine which seal is actually leaking.

Yes, usually is #10 for the shifter shaft not #11 for the output shaft. I actually have never seen #11 leak.

[JingChai]

Ok, I’ll clean out the area and look closer.