Brakes

[seit]

Okay, sob story time:

I was driving around when I noticed a squealing from my driver's side rear. A couple minutes ago I jacked up the car and found out that the brake pad is rubbing the disk (yes, the parking brake was off). Can anyone tell me how this happened and what i can do about it?

The only explanation I can come up with right now is that there is too much fluid in the cylinder.

[curtis73]

Nope, they always drag. Its part of its design and its working properly.

A few reasons why disc brakes squeak; worn pads, glazed rotors, or just plain dirty. Pads are usually installed with some blue gunk on the back (not the face of the friction material) to absorb vibrations. Brakes (by design) will often squeak for the same reason a pencil eraser squeaks. Its just natural. The blue gunk absorbs normal everyday vibes from the pads and prevents noise, but sometimes they stil squeak. It depends also on the type of pads you have. Some friction materials give superior braking torque with the penalty of more noise.

One one end or the other of one of the pads should be a little metal tab. Once the pads wear down, this tab will contact the rotors causing a squeak letting you know its time to change them. Even if one or both pads look like they have plenty of life left its possible that this tab is telling you its time to replace.

If not, a good way to shut them up is to pull them off the rotors, clean the rotors with brake cleaner and resurface the pads. The easiest way to do this is by laying some emery cloth on a flat surface and rubbing the pads face down on it to reveal new friction material. If you're feeling adventerous, use the same emery cloth on the rotors; just enough to brake the shiny surface. When you reassemble you'll need to re-seat the pads (a process almost no one does anymore). To seat the pads, take the car on your street up to 30 mph and do a good hard application. Don't lock them up and don't come to a complete stop. Do this about 6-10 times at varying speeds but at no time should you completely stop. If you absolutely must stop, put it in neutral and get your foot off the brake immediately or pad material will burn in and deposit on the rotor. After you've re-bedded the pads you can return home trying your hardest not to stop the car with the brakes still applied.

This deposition of pad material is the cause of what most people refer to as a warped rotor which in fact doesn't happen. Read more here: http://www.stoptech.com/whitepapers/...otors_myth.htm

[seit]

interesting... but the main problem i had (that made me notice the squeak) was that around turns the car acted like the tire was underinflated and the car felt like it was going into oversteer (note: i'm a FWD) (IMPORTANT: but only when I was turning right) (even when i wasn't on the brake), except the tires are at fine pressures.

I thought worn pads only squeaked when applied. Maybe my pads are super worn?

[pind]

It sounds like you may have a caliper starting to seize up. try removing it, and cleaning / buffing the slider pins, then put it all back together with some high temp anti seize lube. also check that the piston is not starting to stick in the bore on the caliper. good luck

[The Dude]

yeah check your slide pins.

[curtis73]

yep, sounds like a sticky caliper to me.