Oil spots under driver's seat area on a 1999 ML320
 

I just picked up a used 1999 ML320 with 194K miles for my son. Of course, after a day of driving it around and patting ourselves on the back for what a great deal we got on it, we discovered a mystery leak on the driveway. We had driven it several times during the day and had parked it in various places on the driveway. Only after our last trip, did we notice a puddle which seemed to be more water than oil, but definitely a mix. My initial thought was the the condensation on the AC unit had dripped over something oily underneath. This was the only spot on the driveway, so it hadn't occurred after any of our earlier trips.

Anyway, I put some cardboard down and found that there was a very small drip of oil under the driver's seat area. It's actually come off of the frame of the vehicle, but I can't see up to the source of it. It's one of those drips that hangs there forever before a single drop comes off.

I'm brand new to Mercedes, so I don't know if there is a common cause for this model with this mileage. This thread sounded similar:

https://mbworld.org/forums/m-class-w...placement.html

Vehicle drives fine and the oil level is full. Planning to take it into the shop on Monday, but was hoping you all might be able to point me in the right direction.

Thanks!

The 2008 320CDI Diesel is a completely different engine and ML Model (W164) then your 1999 320 Gasoline W163 model ML.

One thing you can do is to keep an eye on it and trace where the oil leak is coming from. It may help to clean up the area around and above the leak then check back later to see where it is coming from. I have heard of mechanics using talcum powder around the suspected area to highlight the source.
Mike

Do you park in an incline?? the leak might travel on the frame..Did you spell something in the car? can you post a picture of the leak? can you look under the car? can you call the previous owner of the car and ask them if they are familiar with the leak??