Fara

So I recently had some new rear tyres installed (255/45R17) onto my 9.5' wide Cup1 replicas.

Previously, the car was running 265/45R17 on the same wheels.

After the install, I've now gained a clicking noise when disengaging the clutch and if the car hits a bump that causes the suspension to move it has now started scrubbing on the outside of the tyre. I could get the arches rolled, but it's odd that this has started after installing SMALLER tyres onto the car.

The clicking noise has me a bit worried - i've been doing some research into ML55's as a tow car for the Rally team that I'm forming with a friend and if it was on that car I'd be convinced it was the rubber end of the torsion bars that had decayed and come loose, which would increase the amount of travel and cause the click as it rattled around a little bit.

Any thoughts? I'd rather not have to pull the torsion bars and re-index them after just to check (Not that it's a difficult job, just very time consuming).

Also, as a note: they jacked the car up from the rear to install these tyres, which I wasn't too happy with as there aren't any good jacking points out the back, however they had already done so when I noticed what they were doing -.-

mytrplseven

did they jack it up using the transaxle as the jack point or some other point on the body? If they used the transaxle to lift the car they may have broken the transmission mount which would allow the tranny and the wheels to slide sideways. Also go on tire rack and compare the width of the tire and tread of the old tires and the new ones. It's possible that you've gotten a tire that's a bit wider than the older one. I did that when I put Cayman 17" wheels on my car and it rubbed the left rear fender lip when making aggressive right turns. I used the tire data to select a tire that was 1/8" narrower and the problem disappeared.

Fara

I'll be under the car tonight to check those transmission mounts. The popping noise could certainly be a failed transmission mount.

As for the tyres, I'm fairly sure the current ones are slightly narrower, but I'll definitely check that out as well.

bad_monkey

FYI - rolling the arches is not so much the case in the rear as pounding the crap out of them with a hammer. If it comes to it, scrape all the crap and underseal off the fold, put masking tape on the lip, heat the paint with a gun, and then pound with a hammer. Work around from the outsides of the arch to the top. I still have more to go. I've also subtly flared my rear quarters bery slightly using the factory jack and wood blocks to spread the load - scary, but slow going gets good results.