Rotational Squeak

[EZ$]

OK, now that I've been able to drive it, I found that I have a really annoying rotational squeak. It only happens when moving, it's coming from the rear of the car, and when the brakes are applied the squeak stops.
Other than the ebrake cable being maybe a bit too tight, causing the rear pads to drag, can anyone think of anything else that may be causing this? Had a friend come up to help check it out, and the rear wheels seem to be dragging a bit which made us think it may be the ebrake, but thought I would see if anyone else has run into this problem, and found another source for the noise. Thanks.

[mosh1999]

So it is only with the rotation of a wheel, half shaft or drive shaft and not an up/down suspension noise?

[Joel Hauser]

my rear brakes squeak a little too, ;)but goes away when I apply a little pressure to the brake pedal. I can't hear it once I reach 2000 RPM and the wind is howling. I just assume it is a slightly warped or uneven rotor. It is the one problem with my roadster that I am not losing sleep over. ;)

[EZ$]

Yup, only with rotation of a wheel. Pretty sure it's not a drive shaft because the noise comes from farther back on the car, and it appears to be speed related, as when you increase the speed it gets faster. Downshifting does not increase the speed of the squeak. It's a constant, doesn't seem to be related to suspension movement. It's driving me crazy, but I guess that's not a very long drive!

[EZ$]

Joel, I can hear it all the time. I'm going to have to check the rotors to see if they could be the issue, and not the ebrake binding on the rear brakes. I do have T-Bird rear discs, and I replaced the rotors with drilled and slotted rotors, but the hole pattern needed to be spread a bit. I wonder if the new bolt hole pattern is slightly off, and causing some interference?

[Al_C]

At first I thought it might be a half-shaft bearing. But then you said when you apply the brakes the squeak stops. If it was a bearing, it would continue making noise as long as it was turning. I believe it has to be rotor / pad related.

[q4stix]

Have you used anti-squeal grease on your pads? The pads are basically in contact with the rotor at all times even if they're not being applied. Since it's effectively skimming the surface with no pressure it can cause it to sing. I had the same issue on my personal car brakes and after removing/reinstalling, cleaning/inspecting, etc, that's what did the trick.

[mosh1999]

Sounds like a brake issue, a couple of things to check; excessive negative camber and inside edge of rim scraping or brake line rubbing?

[EZ$]

Thanks Al. I'll keep checking.

q4stix, I wasn't even aware of any such thing. I'll have to check this out. It would obviously be the easiest fix. Thanks.

[mosh1999]

Probably best to get the rear up on jack stands, put in gear and have someone press the brakes so you can be right there wheel on and wheel off to narrow down the exact location.

[RoadRacer]

Perfect timing.. I noticed the exact same thing yesterday and will be jacking up at the weekend to investigate.

[CraigS]

It's pretty common for the e-brakes to not release fully even w/ nothing wrong. The built-in springs that should return the arm on the caliper to it's rest position may not be strong enough to do that. People often put a compression spring around the cable between it's stationary spot where it locks into the caliper and the lever.

[Norm B]

Make sure the mechanical items are checked then, as q4stix said, get some of the stuff in the picture and follow the instructions. You don't need much and it can make a hard to clean sticky mess if you are not careful.

Norm

[cob427sc]

I had the same problem using a cobra rear and aftermarket replacement calipers. I found that the mounting blocks on the calipers were actually shorter than the original calipers by about 1/8" and not exactly even causing the pad to slightly drag on the rotor causing the squeal. took a while to figure it out and required a small spacer to put the caliper in its proper location. That solved the problem.

[RoadRacer]

FYI, I've had a loud persistent screech for a week or two, and today I found out why.. no idea how but 3 of the 4 pad clips were missing huge chunks. New hardware solved the screech 100%.

148715

[Mark K]

I had the same exact squeak symptoms on my left rear brake. Turns out the caliper hanger wasn't centered on the rotor, and the rotor was just barely contacting it once per revolution. Couple of spacer washers solved the problem.

[EZ$]

Thanks for all the ideas guys. I'm overloaded with work right now, and my TOP expires on Sunday. Once i catch up hopefully I'll have time to check all this out. Then I need to figure a way to remove my speedometer so I can send it back to have it repaired. It won't calibrate.