Had a R53 and now a R52. There was over a 6 month time period between when I sold the hardtop and bought the convertible. The vert seems to have more vibrations then the hardtop. The vert had 46k when I bought it so changed both motor mounts and also put a new belt on. The vibrations increased due to what I believe is the new upper mount (the old was shot) and the new belt that is tighter. I have read about the harmonic balancer pulley but as the vibrations are the worst between 1500 and 2000 rpm (the rear view mirror shakes), and as others have said even with an ATI crank pulley their vibrations still remained, I am chalking up the vibs to the vert frame design and lack of a hard top.

I got thinking about the rattles that I thought were coming from the muffler as well as under the hood. The attached picture reflects where I put simple rubber O-rings (plumbing faucet type that you can buy at Home Depot type store) where the front suspension frame and mid-muffler exhaust brackets bolt to the body. I also placed rubber pads between the black under body braces (not the non painted) and the stainless steel straps that hold the gas tanks in place. I used contact cement to adhere to the braces (there are two).

Knock on wood, the rattles have decreased significantly. I also put a small amount of foam on the tailgate plastic opening handle that I think slaps against the plastic trim when you hit a bump.

 

Thanks - will have to give this a try on mine.

 

I have the M7 Understrut system and that tightened up my R52 a bit. I also added the STB.


So you put the rubber washer between the main and the body correct? So it's a mild dampener?

 

Yes and I installed a rubber o-ring where the passenger side motor mount bolts to the strut tower as well as placing some rubber strips, about 235 mils, between the bottom of the mount and the frame. I cut up some rubber roofing into 1" x 2" strips and then punched holes in the center (see attached, pic shows 1st of three). The bottom of the mount slides through hole so the rest of the mount is cushioned by the rubber. In the world of tight handling all of these do not help, but as I am not autocrossing, I do not see the harm.

Its the cursed vibes at 2k rpm that makes the mirror vision distorted. Mine was not too bad but my efforts have decreased the harmonics. I need to open the mirror attachment point as when you place just a small amount of finger pressure on the mirror, the vibes are eliminated. Wondering if there are some rubber washers up there installed by the factory.