Squealing Rotors?

[aldaran]

Hi. I just replaced all four rotors with drill/slotted with new pads and after about a day, there is a high pitch squealing sound when the brake is lightly applied to slow down in traffic or at a stop. If I apply the brakes a little harder, there isn't a squeal. I have replaced the pads with a higher quality brand and I still hear the squeal. Should I replace the rotors? I purchased the rotors on Ebay so maybe they are cheap. I guess you get what you pay for. Any advice? Sorry, I forgot to mention they are on my 2000 Camaro with disc brakes all around.

[Gary94Formula]

Are the pads loose in the caliper? My brand new truck did the same thing. The pads vibrate/squeal when the brake are applied lightly. Putting them on a little harder stops the vibration and the squeal will go away. I know the mechanic that works on my truck and he called the GMC rep and they told him to use a high temp grease on the back of the pads and it worked. The problem is the grease goes everywhere and makes a mess.
I've also had luck using a very light coating on the back of the pad where it contacts the caliper piston and the claiper mount. Put it on the back of the pads and almost let it dry completely and then install the pads. I used this trick on my wifes 2002 firebird when I did rotors and pads and they work fine.

[Blazer]

Were they new rotors or used ones.
Blazer

[BrdWAtti2d]

You could try anti-squeal compound on the back of the pads as well. I always use it when doing brake jobs. It's kind of messy, but worth the mess not to have brakes that squeal. If you used ceramic pads, a little squeal is kind of inherent.

[aldaran]

Were they new rotors or used ones.
Blazer

Yes, they were a new set coated with nickel so they wouldn't rust.

[aldaran]

Are the pads loose in the caliper? My brand new truck did the same thing. The pads vibrate/squeal when the brake are applied lightly. Putting them on a little harder stops the vibration and the squeal will go away. I know the mechanic that works on my truck and he called the GMC rep and they told him to use a high temp grease on the back of the pads and it worked. The problem is the grease goes everywhere and makes a mess.
I've also had luck using a very light coating on the back of the pad where it contacts the caliper piston and the claiper mount. Put it on the back of the pads and almost let it dry completely and then install the pads. I used this trick on my wifes 2002 firebird when I did rotors and pads and they work fine.

Should I apply this trick to the rear brakes as well or only the front ones? I assume it is the front brakes that are squealing right or do the rear ones do it too?

[ConElite]

You could try anti-squeal compound on the back of the pads as well. I always use it when doing brake jobs. It's kind of messy, but worth the mess not to have brakes that squeal. If you used ceramic pads, a little squeal is kind of inherent.

There is some compound spray that you spray on the back. let it dry a bit and bam. Ill get the name tomorrow. Also just about all brake pads should be installed using some of this anti-squek stuff.

Yes, they were a new set coated with nickel so they wouldn't rust.

They will rust with time. Believe me, Unless they are Billet like the 2 pc units,
all that Zinc coating will come off. Mines did and its been about 6 months.

[Joe 1320]

Brake squeal is typically caused by harmonics of the pad vibrating against the caliper and disk. The factory used a composite paper shim that was tacked to the back of the brake pad. Most times they get thrown out on the first brake job and unless you duplicate that shim, you'll have to use an anti squeal liquid compound to take it's place. Apply it, let it skin over and assemble the brakes. No more squeal.

[aldaran]

Thanks for all the replies. It looks like I have some brakes to work on this weekend. I will let you know how it goes. Thanks again!

[aldaran]

Well, the anti-squeal compound worked perfectly. I got one question, when I was placing the pads back on, I noticed the wear indicators were at the bottom, and the manual said they should be on the top. Would that cause some of the squealing as well? Anyway, I placed them at the top per the service manual. Thanks again!

[Trash man]

that wouldnt cause the noise, those are suppose to make noise when the pads are almost worn out, 90% of the time they just bend away or break off