Hi,
I think I have a leak in my rear differential (1971 280sl, 150,000 mi), because there's an incredible amount of crud collected on the bottom of the unit, and there appears to be a piece of rubber sticking down from the middle of it.
Maybe it's just a clogged vent, as previous posts have noted. However, I have the feeling that some sort of seal needs to be renewed. Are some of them pretty much straightforward to replace, or is this a big operation?
Bruce
1971 Copper 280SL Automatic