Recently, I use the MB jack in the jack hole to raise that part of the car, and then put a jack stand underneath the jack hole where the tube sort of bulges down. Another site suggests you use cut pieces of radiator hose between the stands and the car to protect the car and prevent any sliding. I just go around the car one by one. It is slow, but I feel pretty secure about the car afterwards. On the front, I have never felt good about the control arms because I cannot find a place that seems flat enough.

I have used the diff to jack the car which seemed fine to me. Not sure what the problem could be. But my driveway isn't flat, so it didn't raise both sides of the car the same. So it wasn't has helpful as I would have liked.

If I recall, there is also a cross member below the engine which looked super burly to me. I lifted the car there once too, with no negative consequences. But I have yet to zero in on any one plan that seems best. Good luck.

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1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).