I'm trying to figure out what this front engine noise is. This happens only sometimes, if I'm driving on a flat round going over 45mph in my 81 240D I sometimes hear a noise like the engine is vibrating. Then sometimes I hear the same sound when the engine is under a load(going up a hill).

Another question: When I'm backing up I always hear a "clicking" sound" from the rear of the car. What could this be?

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1981 240D
Click Here To See My Mercedes

Axles. Check the boots to make sure they are not torn.

Can you replace the boots on this car?

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1981 240D
Click Here To See My Mercedes