New Brakes Very Noisy

[matthewb0051]

It was time for new rotors and pads for the wife's Land Rover LR4. I recently replaced the whole kit. I can't find the info but I believe it was Powerstop but am not 100% on that.

Anyway, since replacement the fronts (mainly) have been very noisy. Its not a squeal or squeak. It is more like a grinding and it won't go away. Its almost like the pads are the wrong compound for the rotors but they were paired together by the vendor.

I've done the bedding process 2 times and nothing helps.

The brakes work properly and stop great. But the noise is maddening. I've never had this happen, ever, and I've done brakes on numerous cars over years.

Any thoughts before I just get new pads and start over?

[masraum]

I'd take the front end apart and thoroughly look over both sides and make sure that you don't have something that didn't go back together quite right.

[fastfredracing]

Are they crossdrilled, or slotted? I have seen this several times over . I personally do not like them .

[matthewb0051]

Originally Posted by fastfredracing

Are they crossdrilled, or slotted? I have seen this several times over . I personally do not like them .

No, just regular vented

[Walter_Middie]

My Land Rover has directional pads - never seen that before. That shouldn't cause noise, but something to check.

Are the rotors hot after a drive? This would show if the pads are dragging and making noise.

[onewhippedpuppy]

There’s not a computer calibration required for the new pad thickness is there? Some of the newer computer controlled braking systems have a calibration procedure.

[biosurfer1]

Not sure if it makes a difference or not, but I still bed my pads and rotors when I get new ones. Some manufacturers list procedures but usually they are something like 30-0 easy stop, 60-0 easy stop, 40-0 hard stop, 60-0 hard stop.

Has worked for me over the years.

[matthewb0051]

Originally Posted by biosurfer1

Not sure if it makes a difference or not, but I still bed my pads and rotors when I get new ones. Some manufacturers list procedures but usually they are something like 30-0 easy stop, 60-0 easy stop, 40-0 hard stop, 60-0 hard stop.

Has worked for me over the years.

Oddly enough, I've never had to bed pads/rotors before. But after putting these on and they didn't settle down immediately I did a bedding procedure.

I think the theory is to get them to a temp where the pads get so hot that they put a coating on the rotors. The instructions say it may even take two attempts. It didn't work in this instance.

I replaced pads on this vehicle a few years ago. No bedding, no issues.

[mocha07]

Originally Posted by matthewb0051

No, just regular vented

Did the rotors have coating applied to them,maybe the cause of the noise,slow to bed in the pads.

[legion]

Had a similar issue on the Chevy Van. I bought heavy-duty pads and rotors for the front. Stopped great but squealed like a stuck pig when they got up to temperature. It went away after winter. Did the rears this year and same issue.

[matthewb0051]

Originally Posted by mocha07

Did the rotors have coating applied to them,maybe the cause of the noise,slow to bed in the pads.

I cleaned them w brake cleaner.

I didn't say, the noise for a bit got better, now they are as bad or worse than ever. I just assumed they would wear in.

[911 Rod]

Anti seize on the back of the pads/backers?

[Zeke]

Squealing is eliminated by putting a small chamfer on the leading edge of pads with a file or sandpaper. But you don't have a 'squeal'. Check the wear pattern on the cross hatching on the rotor faces and report back.

[A930Rocket]

Good question. In reverse going very slow, my brakes squeak like crazy.

[rusnak]

I had a pair of rear Zimmerman rotors do that to me once, but after they wore in, they were quiet.

[Nostril Cheese]

Originally Posted by Zeke

Squealing is eliminated by putting a small chamfer on the leading edge of pads with a file or sandpaper. But you don't have a 'squeal'. Check the wear pattern on the cross hatching on the rotor faces and report back.

This...

I also sometimes add a thin layer of anti-squeal paste to the backside of the pads.

Although, Ill bet they just havent been bedded enough

[911boost]

I had to pull the drivers side caliper off my F350 and put some brake grease on the back of the pad, for some reason when it got hot it squeaked and it started out of the blue. The pads still have life and it was stuck to the caliper pretty well.

So what I’m saying is it couod be something minor. You would think the PCCB’s on my 911 were bad until they warm up....

[beepbeep]

If it is grinding and not squeaking, something is not right. Perhaps metal backing plate is touching the inside of rotor hat?

Squeak is OK, grind is not.

[fastfredracing]

I always clean the caliper pistons, and the area where the pads ride in the calipers. I then, put a light smear of brake caliper lube on those surfaces. Anti Seize is not preferred here .
I also make sure that all slides are free , and move with equal force, and I try to pay attention when I am sliding the pistons back in the bore to see if there are any sticky caliper pistons.
If they are Brembo that came with the little isolator pads, , they need those , or they will make noise .
If none of this works, I just advise the customer to turn up the damn radio

[speeder]

Pretty good advice already in this thread. Generally speaking, it's all about getting the calipers really clean where the pads slide in them and applying a very small amount, (tiny), of brake grease to the edges of the pads, (metal part), where they slide in the caliper. I also clean pins really well and replace them if they are galled at all. Sometimes a small file will smooth out burrs.

Basically, anything that causes friction where there is not supposed to be any is bad news. A tiny amount of brake grease on the rim of the piston never hurts, that is where the harmonic vibration that causes squealing occurs.

Something is definitely no bueno if you are hearing grinding. Take them apart immediately and investigate.