52 plate SL500 Vibration

[t5grf]

Posting this on behalf of a friend who has just bought a 52 reg 500 SL.
The car has a pronounced vibration at 90 mph, the main dealer he bought it from has had it back twice to sort the problem the second time around they fitted four new tyres but this has not cured the problem.
I had a quick look around it yesterday and noticed that that the rear drivers side alloy had been badly damaged at some point ( I can't believe the dealer didnt notice this!) which I guess could be causing some of the problem, I also noticed that there is a leak from the front right of the car which seems to be in the area of the suspension fluid resovoir (I can see staining on the front chasis rail) I know nothing about Mercs but understand that the ride height can be raised and lowered, could this leak be the problem and do SL's in general suffer from these types of leaks?

[dazren]

We've got a 52 reg SL500 and it had a front suspension unit replaced under warranty due to leakage back in Oct05. Didn't have the vibration through. The problem was picked up during an end of warranty checkover.

[vincen]

Just bought a 53 plate SL 55 amg same problem, I know you had new tyres but get them to check the rear balance, this improved the problem but did not cure it. I am going to put Bridgestones on replacing BF Goodrich what tyres are you running. The tyre are critical, they do not always get the balance right first time.
Vince