Okay, the car I am working on is a 1989 GXL with 4-piston brake calipers. I recently put new rotors and pads on the front of the car. The previous rotors were grooved pretty badly and too thin to be machined. I reused the calipers because the pistons on each caliper moved smoothly in and out of their respective bores.

The problem I am having is that the right brake is squealing... pretty loudly at that. It only seems to do it when the car has been driven for a little while and the brakes have had a chance to heat up a bit. I have taken off both wheels and inspected everything to make there is no deep grooving or uneven wear. Both sides look pristine. The car does not pull to the right or the left and there is no vibration even when heavy braking is applied. The left side does not experience this squealing at all.

The brake pads came with shims already attached so I just used them as is. I ordered some shims because I thought I might have needed them, but it turned out I did not. I used new pins, clips, et cetera when reinstalling everything. Anyone have any idea on what is going on here?

 

What kind of pads are they? Do the shims have little tabs so when the brake pads are worn to a certian amount they rub onto the rotor? Are they too long?

 

The pads are OEM quality type. Got them off of TireRack when I bought the rotors. No, the shims just sit on the back of the pad. They are actually just a tad bit smaller than the pad itself. I know what you are talking about for the little tabs, but these do not have it nor did the old ones I took off.

 

Chances are that if you hit the brakes a little harder when noise occurs, it will go away. The pads are moving ever so lightly within the caliper causing the noise as the piston rubs the back of the pad. Get some brake anti squeal lube from the parts store and apply to back of pads. It solidifies and becomes an insulator between the pads and pistons.