My '86 300SDL has about 150k miles (242500km) and I'm having a front suspension problem..

Sometimes when I hit a bump on the highway (anywhere from 60-80mph), the front left wheel begins "bouncing". I have to hit the brakes hard to slow the car down before the bouncing stops. The steering wheel shakes violently left and right until I slow down.

I think the vibration of hitting a bump is setting off some kind of harmonic vibration in the front suspension -- exactly the kind of thin (I think) a shock is supposed to dampen.

I looked at the front shocks yesterday. Can't see if there is any oil leaking on the silver "piston" rod because it has a cover over it. The outer housing of the shock looks dry.

My question -- Is the problem front shocks? The shocks do NOT look like the Bilsteins I bought for my other car (black with a coloured stripe on them). These are blue and have a white arrow pointing up that says "TOP". That is the only marking I can find on the shock.

The blue & white shock screams original equipment to me... am I wrong? The PO gave me a huge stack of receipts from the day he bought the car until now, and there is nothing about shocks ever being replaced..

Thanks for any help anyone could provide!

Neal

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