Rhythmic Metal Scraping Sound, Follows Vehicle Speed

[Andratch]

Hi folks,

I just recently acquired a '05 Competition Coupe, and love it to death. I noticed yesterday that when driving, I have a rhythmic metal squeaking sound coming from somewhere on the left side...the type of sound you'd expect if the dust shield was contacting the rotor at one point in its rotation. The squeak gets faster as the car goes faster, so its 1:1 with speed.

I lifted the car off of the ground and spun the wheels by hand, but didn't hear the sound...perhaps not spinning fast enough to hear it.

I went out this morning and did repeated agressive braking from about 70 to 30, and applied the handbrake a few times, figuring there might be something stuck between the pad and rotor....Unfortunately, the sound persists.

I could be wrong, but I don't think it would be a wheel bearing if it goes away with the application of the brakes...

Any other ideas?

[Slideways]

Rocks can get stuck between the rear dust shield and brake rotor. Pushing or tapping the bottom of the dust shield usually dislodges them.

[Andratch]

Rocks can get stuck between the rear dust shield and brake rotor. Pushing or tapping the bottom of the dust shield usually dislodges them.

My dust sheilds are a bit hacked, because the previous owner cut them to install a big brake kit that has since been put back to OEM. I don't see a spot where the dust shields are rubbing right now, but I could have missed something. I suppose I can remove the rotors and see if I find any contact points

[Estoril]

Educated guess: You calipers are binding and you are lightly dragging a pad. The sound disappearing when you brake is the diagnostic. If so, time to rebuild calipers (recommend all of them). Replace pistons with wear marks from binding.

Smaller possibility of a binding slider pin.

[robgill]

Do you have wheel spacers and longer lug bolts? If bolts are too long they can scrape against the e-brake.

[sapote]

Rocks can get stuck between the rear dust shield and brake rotor. Pushing or tapping the bottom of the dust shield usually dislodges them.

Then when he rotated the wheels by hand he should have heard it.

[sapote]

"I went out this morning and did repeated agressive braking from about 70 to 30, and applied the handbrake a few times, figuring there might be something stuck between the pad and rotor....Unfortunately, the sound persists.

I could be wrong, but I don't think it would be a wheel bearing if it goes away with the application of the brakes..."

I'm not clear if you said the noise changed or not when applying brake.

Wheel bearing noise can change when braking as it changed the load on the bearings.

[Andratch]

Hey folks, final update - I went ahead and took off the rotors while I was swapping in new pads over the weekend, and found that the culprit was indeed the dust shield. There was a very, very small spot in contact with the rotor as a result of the previous owner trimming some of the dust cover to fit a BBK. Bent it back into shape, and no more noise.