That joint is straked in place, and you cannot replace it unless you have the proper jig AND a driveshaft balancing machine with the correct adapters to balance a Benz shaft (no one else uses the same ends).

The center rubber mount and bearing can go bad, and I'd check then and the joint, but if the joint is actually loose (that is, front and rear can turn a bit independently), I'd just find a used driveshaft. Should be $150 or so, not worth the effort to fix.

If not, they can be rebuilt, you will have to look around, but the last price I heard was $650.

to check a used shaft, remove the front half and turn the "stub" all the way out -- it must move in all directions smoothly, If it binds, it will vibrate.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!