For those of you that haven't read about my leaking differential I want to impart a lesson that I learned the (almost) hard way!
When I had the oil changed at an instant oil change place (I can't say who!) I was advised to have the differential fluid changed as well. I stupidly agreed. The next day the differential developed a leak. After taking the car back twice I finally gave up and took it to the MB dealer. The "tech" guys at the oil change place DID NOT PUT THE WASHER BACK IN BEFORE TIGHTENING THE DRAIN PLUG!
Fortunately the plug was put in before any real damage was done ( I had planned on taking the car on a 600 mile trip the following day). Unfortunately I'm now in a battle with the company to get them to cover the cost of their mistake.
Moral: Instant oil change places may be fine for a domestic US car, but with a Mercedes-Benz you enter at your own peril!:mad