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Brakes Squeal

Hello everyone. I drive a "02 Accord. Recently I replaced my front disc brakes with new ceramic ones. Note though that this is the first time I’ve done anything since we bought the car new. It currently has 82,xxx miles so the original brakes lasted quite some time (even when I replaced them there was still quite a bit of “meat” on the brakes)! Now when I did the brakes, all I did was just swap out old pads for new ones. About a month later, my brakes started to squeal (not much, but just enough to drive me crazy) Is there anything that I can do to stop the squeals? Also note that I have rear drums and my dad helped me with them, and he didn’t use any of the grease that came with the new pads.

This probably the most common mistake shadetree mechanics make. They replace the pads and leave the used rotors on the vehicle. And then they can’t figure out why the brakes make noise after the brake job.

The problem occurs between the friction surfaces. If the friction surfaces between the new brake pads doesn’t match the friction surfaces of the old rotors, the new brake pads can’t seat or embed themselves into the old rotors properly. This causes mismatched friction surfaces causing the brake components to vibrate to frequency that can be heard. Or a squeal. And the squeal will probably get worse.

If you want to do the brake job correctly, replace both the pads and rotors with components that meet or exceeds the OEM specifications. This includes pads with the proper friction material. And then follow any break-in procedures included with the brake pads.

Tester

The problem you are having is because you did not have the rotors machined. When they wear, the outer part of the radius wears faster than the inner causing a gap in the outer contact area. You can use a disc quiet backing compound for the pads and this may reduce the noise. However the only way to do it right and be sure it goes away is to do the brakes again and get the rotors turned(machined) flat. If not to many miles have passed, you might even be able to re-use the pads. Otherwise get new pads too because they will have worn un-evenly.

Thank you both! I thought that was the problem. My dad was too lazy to replace the rotors… I bought a Hayes manual for my car and it says that when replacing the pads to sand down the rotors with a heavy grit sandpaper. Will doing that decrease the squeals?

The sanding might decrease the squeals, but they might come back. Sanding the rotor breaks the glaze and helps the pads wear into the rotor better/faster. But it still doesn’t address the issue of the rotor surfaces not being parallel. You can try to see if it works, but if it doesn’t, you’ll be doing the brake job a 3rd time. Pick up a pair of new ones and pop `em on and be done with it, after cleaning them and sanding them if you like. You’re lucky this generation of accord has rotors much easier to replace than the last generation.

If you’ve got the time, try the sanding, might be all you need.