Which Differential? How can I determine?
 

Before changing the differential oil on my '87 300TD I have read I need to determine if I have limited-slip or not. Is it possible this vehicle would even have limited-slip and if so, how do I make that determination?
Thanks
Steve

No USA version W124 car came with limited slip. A few diesels from 1990-93 had ASD (auto locking diff). Also the 4-matic differential was the auto locking style.

The odds that a limited slip has been added are virtually nil.

That said, with any car it is easy to tell if it is limited slip or not. Simply raise both rear wheels safely and put the transmission in neutral. Turn one rear wheel forward while observing the other. If the other wheel also turns forward, it is limited slip. If the other wheel turns backwards (opposite direction) it is a standard differential.

Have a great day,

Thank-you.
Now I feel safe to go drain & fill.
Love this car!!
Just had my neighbor complete the NH inspection and he spent considerable time checking brakes, steering, suspension and assorted other things. He looked HARD for rust. Other than agreeing that the tires will need R&R, it got the clean bill of health that I expected. He knows I'm an auto freak and allows me to use his facility 24-7 (what a neighbor). I think he was sweating my acquisition as I drove it to its new home nearly as much as I was.
Back to work on the girl . . .
Steve