I have owned my 1991 420SEL for about 1.5 years. When I purchased the car (from a dealer), I knew that it needed new tires all around. I immediately took it to a trusted and well recommended MBNZ mechanic. He recommended the Michelin MXV4 Plus. While checking out the car, he stated that the upper and lower control arm bushing were shot on the left side and so I had them replaced. The mechanic recommended Winston tires for the tire replacement and alignment and so I had all four tires replaced and the alignment done there. The trouble began when I got the car back. It drives great at speeds under 55+ MPH. But faster than 65 MPH on a not-so-smooth road and it drives like a dump truck - the roughest ride I have ever been in short of an SUV or truck. I have gone back to my regular mechanic and several other recommended mechanics (some that specialize in suspension). I had all 4 shocks replace with Boge Automatics (upon recomendation). I have had the suspension checked from top to bottom, the engine, trans, and differential mounts checked, and the car re-aligned and tires re-balanced too many time to mention. It appears to get a bit better but never the smooth ride expected from a MBNZ of this caliber. I should note that the degree of rough ride varies from day to day and road to road. The bouncing had begun to loosen panels within the car and now some interior parts are ratteling.
Help!!! - My mechanics don't know where to turn and I am tired of spending money on this problem.
A great deal of gratitude would be in order for anyone who could give me any clues.
P.S. - The car has about 98K miles on it.
[Edited by mrbroche on 05-28-2001 at 06:43 PM]