I just bought a 1983 Merecedes 300 SD Turbo with 177,000. My father changed all the belts on it and ever since it has been making a horible low pitched rubbing noise when turning right, but not left. The noise also happens when parked in reverse, but not as extreme. I loosened the power steering pump belt a little, thinking it might have been too tight, but it still makes the noise. We checked the wheel bearings and brakes on the front wheels (the noise is defininitely conming from the front driver's side area) and they were fine. Some people have said it could be the pump. Any suggestions?

 

Does it occur when the vehicle is moving or stationary? For moving, check the tie rod ends for contact with rims or tires. Is the power steering pump reservior full? Explain parked in reverse?

 

remove all the belts and try.

does it still make noise?

 

The car makes a dull vibration when sitting still in reverse (with my foot on the brake) it really intensifies when moving and going around a right hand turn. Although not an uphill right hand turn--which leads me to believe that a shift in weight distribution is causing the noise. Perhaps a motor mount?

 

And yes the power steering reservior is full. I tried loosening and tightening the belts to see if that made a difference, and I could not tell a difference.

 

A bad mount will transfera lot of vibration into the frame. Push on the valve cover from the side(s) to see how resilent the mounts if you can't do a visual due to the heat/fuel shields. Also on the SD, the fan blades can contact the radiator shroud when the mounts fail. It's also possible the allen bolt holding the motorto the mount could have fallen out. Inspect that from below. I've seen motors sitting sideways in the frame due to failed mounts.

 

Ok, so I got the car inspected and the left motor mount was bad. Otherwise, the car passed, after they replaced the left motor mount. I was hoping that would solve the "noise when turning right problem," and it definitely lessened the amount of noise, butdidn'tsolve it completely.There is still a low pitched noise when you make a 90 degree right turn. Before the motor mount was changed it made a loud sound when only slighty turning the wheel right.

 

I had a similar sound with my 190D. It sounded harsh when I made sharp right turns or went of a curb. It turned out to be a bad steering dampener. It is a cheap part that you could most likely do yourself. I paid my local guy 90 buck for labor and parts and it took care of the problem. good luck