I havent seen it on a Benz personally, but my wife had a '97 neon, metal-layered-sandwitch head gasket- a known failure point on early neons - it caused her to lose about a qt every few weeks, from dripping out the back of the engine (and onto our apartment's parking lot). Oil leaking out of an engine does not rule out a leaking head gasket...

...but its one of the worst places to have one.

-John

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2009 Kia Sedona
2009 Honda Odyssey EX-L
12006 Jetta Pumpe Duse
(insert Mercedes here)

Husband, Father, sometimes friend =)