For 190e.....check the bushes in the links for the rear suspension. They may be torn,melted or whatever, but the centre wont be concentric to the outer part of the bush( with the weight of the car on the bush).
Later links are more heavy duty.
You might also check the condition of the couplings on the tailshaft. The coupling at the transmission end is more likely to have "chopped out".
A good test is to "kangaroo" the car ...LIGHTLY... each time the throttle direction is changed , CLUNK! CLUNK!......