Why do I hear a high-pitched noise whenever I step on the brakes?

Question

I can only hear them if roll down the windows. I also just had my brake pads replaced recently. What could be the problem? Thanks.

Answer 1

unless you got 100% ceramic brake pads (which are usually over $70), chances are you got semi-metallic ones, these actually contain bits of metal in them, and when the pad wears down to a point were there is a large enough piece of metal they can squeak.  This can be solved by either removing the pads and scrubbing them on concrete or using sandpaper to wear through the metal causing the noise, or you can just wait till the rotor wears it down through normal use.  If you bought really cheap pads these chunks of metal can be quite large and cause damage to your rotors.

also the pads can squeak were they contact the piston of the caliper when your press the brakes, any imperfections in your rotors can cause them to shift around a bit and squeak. This can be solved by putting a little grease on the BACK of your brake pads.

Could also be the wheel bearings but they usually STOP squeaking when you hit the brakes.

Answer 2

Well if the pads are new, - then it shouldn't be the "squeakers" rubbing on disks (to tell you they are worn out)-- But I worked in a foreign car shop (on French cars), - and the Renault in early 70s had a brake pad problem,. some sounded loud enough to be a a a train coming to a RR crossing! Nobody in US or France could figure out how to stop it for about 8 months! And worst of all not all the same model cars had the same problem!

The pads were so tight in frame that the metal was "squeezed up tight" from expansion when brakes applied, this made horrendous vibrations!    

The solution was to grind a small amount off one end of brake pad where it fit in the caliper frame - the noise was vibrationbecausee the pads fitting too tight in the frame!  So you might want to check to see if  pads fit too tight, and have no endplay,- they should have at least .010 - .015 space between one end and frame!

It was hard to believe such an easy solution was available after all the things we tried to stop them before! We cut crosshatch patterns in brake pad material, drilled holes in it, put pencil lead in them, tried pads made out of other materials by a number of manufacturers! Nothing seemed to help much!

Sometimes the "silicone grease" that comes with better makes of pads, will help a lot applied between caliper piston and "claw" on other side where it fits over brake pads!

Answer 3

Often times the high pitched squeal is from the back of the pad viberating against the caliper and or piston. Some anti squeal on the BACK of the pad will stop it. It should have been done when the pads were installed!

Answer 4

they didn't sand them smooth so there are burrs rubbing on your rotors

Answer 5

Your brake pads would be worn and the circlip is rubbing on the brake rotor/disk. Buy and install new brake pads and you should be sweet as. Or if they are high performance pads then they always aqueel there meant for a race track so unless u are going like 200kmpr they will always squeel.

Answer 6

you probably bought the real cheap pads

the cheap ones will squeal should have spent the money and got the good pads. they are more expensive but well worth it  if you haven't drove very far take them back off and return them to the parts store and tell them you don't like them and want better ones they will exchange the pads for you but you will have to pay the difference of course