I'm about to buy (tomorrow morning!) a 1998 SL500 with 116,000 miles. I took it to a very well-known independent mechanic and he came back with just a few mechanical problems (valve cover gasket, etc.)

One thing that concerns me is that on my current car (Saab 9-3) I needed a $1000 engine mount replacement when my mounts failed, and the symptom was that the engine was moving back and forth when changing gears while parked (put on the brakes and move the transmission into reverse and the engine moved a few inches backwards, move it into drive and the engine moved forwards).

I did this test on the SL, and sure enough, the engine moves while changing gears in a running, stationary car. So I figured the engine mounts on this SL must be shot too. However, I asked the mechanic to specifically check this out and he said that the mounts are fine and that the engine moves forward and backwards by design. Is this correct? I can understand if it is, but want to check with the experts.

Also, the car vibrates somewhat at idle, and they said that this was just typical of the engine. I can feel the vibration of the engine in the car and thought it was an idle problem but they said that it's not an issue -- are they correct?

I've searched the forum for these two issues but can't find anything detailing them. I'd appreciate any feedback before I go buy the car.

Thanks for your help with this.
Amal

 

In your PPI, is there a no fault clause? It is good to be the best but how does he stand behind his report? Does he repair and profit?
I have not owned a late 90's M119 engine MB, however the MB's I have owned were smooth at idle, or the entire RPM range for that matter. Motor mounts are flexible, and do need replacement, but forward to back is not the direction of the torque in a rear drive setup., is it?
How are the service records? Is the car priced for perfection? Good luck and welcome to the forum. Where in the world are you?

 

It sounds like the engine mounts to me. Idle should be smooth with little to no vibration.