Mercedes-Benz: Clunking Noises Heard During Acceleration And Throttle Lift Off

Mercedes-Benz Tech Tip: Clunking Noises Heard During Acceleration And Throttle Lift Off

Mercedes-Benz owners may complain of a single throttle lift-off clunking noise from the side shaft when first taking off (audible at the outboard end). Also, the clunk is heard once when changing from forward to reverse.

Figure 1


MODELS

All Mercedes-Benz cars with front-wheel drive and 4×4 vehicles.

COMPLAINT
Single throttle lift-off clunking noise from the side shaft when first taking off (audible at the outboard end). Also, the clunk is heard once when changing from forward to reverse.

CAUSE
If the complaint is eliminated by experimentally loosening the outboard collar nut by one turn, the complaint is likely due to micro movement in the connection between the wheel bearing inner race and the joint housing of the side shaft.

Note: The collar nut must always be replaced after being loosened and must be tightened to the specified torque.

Figure 2


REMEDY

Coat contact surface of the shaft with wheel bearing with Molykote paint. To do this, proceed as follows:
1. Remove outboard side shafts.
2. Clean contact surface A (see Figure 1) making sure it is free of debris and oil.
3. Coat contact surface A (see Figure 2) with Molykote and leave to dry for one hour.
4. Reinstall the side shafts.

Courtesy of ALLDATA.

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