Mercedes-Benz W124 propshaft rumble and joints
Mercedes-Benz W124 propshaft rumbles or vibrates under acceleration, what causes it?
The most common cause is a worn rubber flex joint (guibo) whose rubber has lost its shape and whose bolts have loosened. The propshaft centring bushings and the centre support bearing can also be worn. Replacing the joint and balancing the propshaft has removed the rumble.
Which way does the Mercedes-Benz W124 propshaft centre nut open and what is the tightening torque?
The nut has a normal right-hand thread, so it opens counterclockwise when viewed from the rear. Open-end wrenches of 41 mm and 46 mm help when the nut is tight. The tightening torque is 30–40 Nm, and the nut should always be replaced.
What should be done to the Mercedes-Benz W124 propshaft before disassembly and when reassembling?
The propshaft is balanced as a whole, so mark the halves and flanges before disassembly and reassemble them in the same position. Otherwise the balance is lost and the rumble may remain. Tighten the rear end first, then the front end and finally the support bearing bolts.