[Fluteguy]

I consulted the dealer about this problem..and paid big bucks for it! The following was the explanation I got. The vibration (shimmy) CAN be caused by any (or all) of the following. Bad shocks, bent wheel, bad bushings on control arms (lower and upper), bad tires.

According to the service manager the most common is flat spotted tires caused by the weight of the car. Evidently, the W140 body style is considerably heavier that the tires are capable of supporting when left sitting overnight. He increased the tire pressure to 40 PSI in the front and VOILA, no vibration. Some tires are not capable of supporting the weight (mine were Falkens, bought by the PO) and some are (I have Continentals on it and they seem to be holding up).

If you do this I take no responsibility and of course your ride will not be nearly as soft and comfortable.

 

[Fluteguy]

The faster you go the more aerodynamic lift your car gets and it literally starts to lift off of the pavement (think of the bottom of an jet wing and you'll understand). This is why the formula one cars have all the fancy multmillion dollar spoilers on them- to force the car back down onto the track. When you go faster the car and tires begin to lift up causing less weight on the tire, suspension, etc. On the BMW 850i's the suspension would automatically lower itself above 100 MPH to create more drag to keep the car on the road (in addition to a nifty "hunkered down" look!).

If the shimmy has started to happen all of the time it's possible that your tires have been damaged like mine were. I replaced mine with Continental ContiTourings and so far (with fingers crossed) the problem hasn't come back. The Continentals are what they're putting an the new MB's as standard tires, or at least they were this summer when I changed mine.

 

[Fluteguy]

I think that once again we need to go back to the weight of the car and the height factor. After 94 the car was lowered an inch and a some of the heavier options were deleted (parking assist anntennae for one). The original list price for my 93 was $97,500. The '94's dropped almost $15,000 in price due to MB leaving out some of the heavier stuff.Again, weight and height!