97 Mitubishi Eclipse 2.4L non turbo...

I am hoping someone can help me diagnose this problem. Just had new tires put on the car and then put about 60 miles on it --- everything great. Next day, my wife drives 5 miles then starts to hear a rasping sound from the right front passenger wheel. Before the tire change, no problems/sounds symptoms at all and pads and rotors were replaced about 2 years ago.

Now, after the new tires, the rasping is notceable at lower speeds especially but it's not ALWAYS there. No pulling when driving or braking but when I tried riding the brakes at high speed I get a pulsing in the pedal that wasn't there before and a groan when stopping...sometimes. I pulled the wheel off, nothing seems to be rubbing or stuck.

Any thoughts? My only guess is that the tire shop overtorqued the lug nuts (they say on ticket 100 f/lbs) which warped the rotor but thats only a guess. Not easy to take it back to the shop either (sigh) since it was one of those wholesale clubs that only install/don't do mechanical work and it's 40 miles away!

thanks much in advance, ggaarryy

I would say your pads are worn out especially after 2 years. Or could just have some dust between the pads and rotor.

I dont think it is even possible to warp a rotor by over tightening a lug nut, sense your doing nothing to the surface of the rotor which mates with the pads, plus it would mean you warped the hub with it. The stud would snap off way before that would happen.

thanks...I spoke with the installer who remembered that I still had life left on the pads but could offer no other explanation. Spraying the caliper with brake cleaner didn't help either.

I guess it could just be coincidental (especially with my luck) that it would show up right after I got new tires but I was hoping that there might be some other explanation with an easier solution.

ggaarryy

Look for loose things in the area of the wheel/tire that might be rubbing. I've bent the backing plate for my rotors accidentally and it was rubbing.

try getting the nose of the car in the air and run the engine with the trans in first and let the wheels spin freely under engine power. play with the steering and see if that makes a difference, get up in the area of the noise and listen for the sound. A mechanics stethescope might help depending on how loud your engine is

Originally posted by RoninEclipse2G
I've bent the backing plate for my rotors accidentally and it was rubbing.

x2. This would be my first guess, look into that

well, turns out that the passenger side inner brake pad was worn down to the metal causing the rasping/grinding sound, although the outer front pad looked fine. Looked at driver side pads and both were worn down to nothing. Rotors on both horribly scored and almost certainly warped.

About 60k miles on the semi metalilc pads and rotors. Funny thing, until the grinding started after the tire change, there was no indication of ANY brake wear problem -- quiet even braking, no sounds, no vibrations (not even the typical warning noises that come from worn pads) and the brakes even passed safety inspection a week earlier.

The installer swears he didn't overtorque lug nuts and even if he did, a warped rotor wouldn't cause pad wear like that to happen.

Aside from just miles or overtorquing, any thoughts on what could cause the extreme wear on the pads...and even more confusing...why would the one outside pad be okay?

thanks ggaarryy