Please help me pinpoint oil leak..
 

Hi all,
Please see the attached photo...angle is from the passenger side looking forward at the back of the bell housing/ rear main.
On my 2000 E-320(WITH 49K),I discovered this.It is oil, not trans fluid.
It was about to drip..so I cleaned it off.
The photo was taken after I then drove 2 days/100 miles.
I appears to be coming out of the "vent" and not the actual seal in front of that.
Any Ideas???
What would/could cause a relatively new, low mile car to start this?
How serious is it?
How big of job ($$$) to fix?
Help:confused:
Thanks!!!!

look up inside the bellhousing at the front of the trans and at the rear engine seal. one of those is likely your culprit. Judging by the color and the car's age/mileage I'd say thats trans fluid but it does only seem to be toward the engine side so it may be oil. hard to tell from that picture.

i am working on the same v6 engine in the c class.same year same problem.the plate that holds the rear main oil seal was cracked due to the bolt that holds the excentric weight on the balance shaft coming loose but i am replacing the seal as well[needed a new plate but surprise.......it was in stock].

That is likely the rear main seal. Pretty classic. But i'm not experienced on the MB so much.

i just was able to get a good look inside...found nothing that indidcates where its coming from...everything inside the "vent" looks dry:confused:

Would agree, probably main seal or the plate the main seal presses in to. Does look a bit more like ATF to me too though. I don't "think" your torque converter has a drain plug, but if you want to double-check, possibly that plug might be dribbling a little and slinging the fluid around inside the bell housing, that would explain why you can't find where it's coming from. Bottom line is that if the car doesn't "leave it's mark" on the floor or driveway overnight, probably not worth pursuing IMHO.
Gilly