Changing rear diff oil on E300's?
 

Has anyone changed the fluid in their rear axles in their E300's? Just curious. I'd kinda like to change mine out for some fresh fluid after 50k.

I just changed the rear diff oil in my SDL to RedLine last week. It was a really straight forward job. There's a drain plug and a fill plug. It will spill out of the fill plug when it's full. My owner's manual says that it takes 1.2 quarts of fluid.

I used RedLine 75w-90 even though the manual calls for 85w-90... no ill effects yet.

Well I'm just not sure if my car requires a limited slip additive for the diff, and would hate to put in the wrong stuff.

:o Didn't think about the limited slip. Mercedes didn't give us LSDs on diesels back in the 80s. :(

Your owner's manual doesn't give you any advice on changing the fluid? My owner's manual covers almost every aspect of vehicle maintenance in fairly good detail.

I think marketing has gotten the best of the owners manual :( They say the trans fluid is a 'lifetime' fluid, and they dont mention changing the diff fluid whatsoever. I will have to double check again but am pretty sure the diff isn't even mentioned in the manual.

I don't know anything about the e300. I have
however read a few gm manuals from the 60's
+70's. The advice given on changing rear-end fluid
was not to. If the rear-end presents a problem
requiring it to be drained so it can be examined/
taken apart then change the fluid.
I don't agree with this. Today when I changed
the (probably) 34 year old fluid in a 1970 chevy
c-10 it was dark brown and seemed to come out
in clumps, though there was no solid material.
It seemed to have a consistency more like motor oil.
In may have been just a buildup of moisture but
in any case I'm sure provided less than ideal
lubrication. Having experienced rear-end problems,
I'm sure this was good pm. If you are shopping for
a 14mm hex let me know. I sold the 82' sd and
don't really need it.