I had a chance today to take a closer look at my oil leak. I am 99% sure it is not the headgasket. With a mirror and penlight I was able to see just about all of the intake side and the back. No leaks there. The rear main was the next possibility. There are two access holes, one a plate on the front of the bell housing, and the other a round plastic plug on the back side. I took both of them off, the bell housing was dry. Am I correct in assuming that this should have been wet with oil if the rear main is leaking? It looks as though the oil is coming from above the starter in the area of the oil filter housing. I will pull the starter out friday for a closer look. Is that filter housing bolted to the block? Has anyone seen a leak like this that wasn't the head or rear seal? It is definately worse when the car is cold too, it leaves a trail in the snow. I let it sit overnight and checked the oil in the morning. It had only gone down a half quart after my 2000 mile trip home. I hate oil leaks, help me! Brent

That is precisely why I am looking at it myself. I had an opportunistic shop in Palm Desert CA tell me it was the rear seal. I am now almost positive it is not. It is definately not the valve cover gasket though. It sounds as though there are some connections at the base of the oil filter housing. The housing itself is a bolt on and there is an oil cooler also. Believe me I hope it is something as inexpensive as a valve cover gasket.

All of the M104 engines that leak from the head gasket, leak on the EXHAUST side at the front & or rear!

Also, if the seal for the oil filter lid or something therein is weak, it could leak.

Thanks for the responses. I found out AFTER I spent a bunch of time looking on the wrong side of the engine that the leaks are on the easy side from Gwagen USA as well. The oil filter housing itself is dry around the seal on top. There is appearantly an oil to water cooler attached to this housing under the intake manifold. Have you guys ever seen problems with leaks from this part? I will have time tomorrow to remove the starter and get a closer look. How about the rear main and a dry bellhousing. Is it possible for oil to leak through the rear main and not puddle in the bottom?

On the 1990-93 300SL & the 1992-93 300SE the oil/water cooler WAS a problem, MB modified the radiator in the cooler due to high fail rate.