I got a brand new differential for my 190 using car-part, it had 17000km on it cause the donor car got rear ended. Since I put that differential in, the car floats on the roads, it used to vibrate in all sorts of ways, no more. In worst case scenarion, I'd go look, you might get lucky and find a donor that was even more pampered then yours, a lot of people, including me love these cars so much they forget to eat and breathe
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