Sounds like fun! It seems that you are getting to the "rearend" of your problems! I have heard in the past that when you replace or repair something in a driveline, the things that follow are not far behind. I am pretty confident that you will get it all sorted out, however I think that a Mercedes Benz is far easier to work on than any american car (except the old ones). You will find that with any Mercedes they are built to be repaired. They put things in the right places to get access and etc..
The rear end going out is not common. It could have been run dry of lubricant, but I have never seen one go bad. The half shafts do get a little problematic at higher mileage, but my SL has 133k on it and has the same driveline, the only thing that has been replaced is the rubber flex discs. Do you live in a bumpy neighborhood? go fourwheeling on the weekends? Maybe it is time to get a second opinion on your repairs? I had a 1973 280C that was in the shop all week, I would get it out Friday, by the time the weekend was over something else would go wrong and back in the shop on Monday. I eventually replaced the entire driveline (except the rear end), but the car had 450,000 miles on it, same transmission, but the half shafts and center bearing were replaced.
Are you in the MB club? if not you should join, other members including myself will be glad to help you out and take a look at your car. Good luck!
Brian

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Brian W. Heitman

www.MBCA.org/northtexas

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