Tyre rubbing - Cause???

[Paul_D]

Hi guys,

I've got a 1998 M3 Evo.

Coming home yesterday I heard a funny noise going over bumps.
Today I listened more carefully and there was a definite rubbing noise over bumps.

So I had a look and the left rear tyre has been rubbing on the arch.

Could a knackered damper allow too much travel and create this problem?

To add to the confusion I recently had the arch repaired that side, and looking at it carefully it seems different to the other side in that the bottom flat section is slightly thicker and then the angled section does not go up as steeply as the other side.
BUT......the people I car share with say they've heard that rubbing noise quite a few times before, albeit not as bad as it is now.

Additionally I've recently changed the rear tyres from Eagle F1 GSD3's to Eagle F1 Asymmetric's.
I'm not sure if these are slightly wider / squarer or not?

The car is on standard M3 suspension, standard wheels and tyre sizes.

What do you think is the most likely suspect?
Has the slightly thicker arch just highlighted a problem with the damper? (this would be my guess, but I don't know if failed dampers cause that much additional travel )

Cheers,

[cableguy]

Welcome. ;)

Probably best to get a good Independent to look at it to ascertain the cause. More than likely the tyre being slightly more square then OEM and maybe worth getting the arches rolled to eliminate future rubbing.

C.

[Doc Matt]

Hi Paul, welcome.

Basically you are right, over time the car will bounce a little further as the shocks wear out and the new arch has added to the rubbing.

Is it normal suspension and whats the mileage?:)

[Paul_D]

Hi guys, thanks for the welcome.

(I was sure I'd posted on here before though! Must be mistaken)

Yep, it's standard suspension and the car has done about 83,000 miles.

[peppernick]

Also look out for potentially a snapped rear spring. Can happen.

If you're running standard wheels and tyre size, it's very unlikely the different sidewall profile of your new tyres that is causing the rubbing. OEM settings you'll have plenty of clearance allowance.

[Paul_D]

Thanks people.

Well I've just managed to have a chat with my mechanic and he thinks it'll be the new arch being too thick.

He said that even with a truly knackered shock absorber the wheel should be able to go right up into the arch without any tyre rubbing. (On standard wheels and tyres obviously)

He thinks the standard arches are probably quite close the tyres, and the extra few millimeters and different shape inside the arch is by far the most likely cause.

Looks like I'll have to go back up the bodyshop that did the arch work and explain the situation.
Hopefully they'll do some corrective work for free if I'm nice to them.

[cableguy]

If the new arch isn't rolled then it should be an easy fix to a competent bodyshop proficient in the art of arch rolling. ;)

C.

[Styler]

How close is the tyre wall to the arch on the non modified side? if it is very close than the modification that has increased the thickness of the arch lining could well be the answer.

If you look at your car parked on a flat surface, does it look evenly settled? if not, than as others have said nackered shocks and/or springs could be the problem.