The front brakes recently started squealing very loudly every time they are applied. The pads are semi metalic with barely 5000 miles of normal use on them. The noise will go away temporarily if I clean the pads with brake clean, but the noise always returns within a few days. The rotors are not glazed nor overheated. I have applied Disc Brake Quiet to the pads with no change. Due to the previous owner, the tension springs that go in the top of the pads are missing. Would this contribute to/cause the noise? Is my only recourse to turn the rotors?
Brake squeal
- Thread starter KMinAF
- Start date
Yes, you need those springs, or the pads will vibrate around terribly. You should also have two wire springs that hook into the edges of the pads to spread them apart. There are little holes in the pad edges for this. If they're missing it will also contribute to a squeal.
If the rotors were changed with the pads there's no reason to turn them. I'd avoid ever turning/cutting a rotor. If it's worn unevenly replace it.
The biggest causes I see for brake squeals are:
1. Sticking slide pins. They cause the pads to drag. Greasing the pins sometimes isn't enough to make them slide freely. Remove the rubber bushing from the caliper body and use a round file to clean the rust out of the hole, then paint the caliper there to prevent return of rust. Then put the rubber bushing back in and grease the pins. Should slide much easier.
2. Pads not sliding freely in the caliper bracket. Aftermarket pads these days are garbage, for the most part. I install about 15 sets of brake pads a week, and about 10 of those sets have pad backing plates that are stamped poorly and don't fit in the caliper right. If they don't slide freely in the caliper, they will drag and squeal. Get a file and clean up the contact points so they fit the calipers with about .020" gap for heat expansion and future rust swelling. Paint the edges to prevent rust when you're done filing.
3. Sticking caliper pistons (or bad brake hoses). If the caliper pistons didn't push back easily when you did the brakes, the calipers might be bad. Sticking calipers will cause squeal. Open the brake bleeder and see if the caliper is easier to push back. If it's not then the caliper is bad. If it is easier, your brake hose is bad on that wheel.
4. Missing anti-rattle/anti-squeal hardware. You already said this was missing, so fix it.
If the rotors were changed with the pads there's no reason to turn them. I'd avoid ever turning/cutting a rotor. If it's worn unevenly replace it.
The biggest causes I see for brake squeals are:
1. Sticking slide pins. They cause the pads to drag. Greasing the pins sometimes isn't enough to make them slide freely. Remove the rubber bushing from the caliper body and use a round file to clean the rust out of the hole, then paint the caliper there to prevent return of rust. Then put the rubber bushing back in and grease the pins. Should slide much easier.
2. Pads not sliding freely in the caliper bracket. Aftermarket pads these days are garbage, for the most part. I install about 15 sets of brake pads a week, and about 10 of those sets have pad backing plates that are stamped poorly and don't fit in the caliper right. If they don't slide freely in the caliper, they will drag and squeal. Get a file and clean up the contact points so they fit the calipers with about .020" gap for heat expansion and future rust swelling. Paint the edges to prevent rust when you're done filing.
3. Sticking caliper pistons (or bad brake hoses). If the caliper pistons didn't push back easily when you did the brakes, the calipers might be bad. Sticking calipers will cause squeal. Open the brake bleeder and see if the caliper is easier to push back. If it's not then the caliper is bad. If it is easier, your brake hose is bad on that wheel.
4. Missing anti-rattle/anti-squeal hardware. You already said this was missing, so fix it.
Sand the pads a tad and break them in properly. Noise will go away. BUt you also need the hardware.
When you sand it do it with something fairly rough (around 60 grit is what I use). Another thing I've found is taking the hard 90* edge off pads helps as well. Sand the edge down just a bit so it's got a 45* on the edge rather than the 90*. Doesn't have to be much, you don't want to be taking away significant pad surface area, just trying to minimize having a hard edge for it to possibly bite/grab/shudder on, thus causing noise.
And again, make sure you have the shims/springs/etc that are included with the pads to prevent noise
And again, make sure you have the shims/springs/etc that are included with the pads to prevent noise