Own a 1979 300sd and need to replace the differential oil. Would like to know what type of oil I can use that is equivalent to the mercedes dealer oil. Is anyone here familiar with this car? Would like to know if it is equiped with a Limited Slip Differential(LSD). I know that there are gear oils that I can use and all that depends on wether or not it is LSD. Someone once told me that if I lift the center rear of the car and turned one wheel one direction the opposite wheel will turn the same direction and that confirms an LSD. Can anyone qualify that statement? Would appreciate recommendations?

Any good quality 80w-90 GL4 or GL5 hypoid oil will work.
That car never came with an LSD.

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