Brake Problem - Unfixable Noise - HELP

I have noise during breaking under 30 mph. The noise seems to happen only on one part of the disk. If you imagine the rotor like a clock the noise happens when the rotor is at 2pm, as an example, but everywhere else it’s fine. So if you were going slow enough and could life off the brake in time then get back on it you could skip the noise. The noise comes from the front left. I’ve replaced the pads and rotors three times (as a set). The car is an 03 with 42k miles, suburb driving at low speeds and no hard braking. It’s fine for a week or so with the new rotor pad set then the noise comes back again. The car is stock. The noise is not a grinding it’s more like fingernails on a chalkboard. Is this a caliper issue? Has anyone ever had a reoccuring issue like this?

Have you replaced the brake hardware (anti rattle clips) and used plenty of brake lube anywhere the pads or hardware would be subject to vibration? Lack of lubrication is the most common cause of squeaks and squeals.

CRC makes a product called “De-Squeak” that works pretty good…

Do you put your lug nuts back on with the correct amount of torque? Have you completely cleaned the rotor’s mating surface with the hub?

Yes and yes. Going back again the mechanic said the calipers look dry and he put in new grease. Everything else checked out, but the noise did not improve or worsen. Wheel bearing perhaps? Next drive around I’ll check to see if that side is hotter.

I’m not in the US, so wouldn’t help.

The mechanics I’ve seen use a lug nut air gun. I don’t know if it’s torqued or not, I’ve never seen them check the torque. They’ve put them on tight. Took me some effort to take them off when I got a flat in the back.

I don’t know if the mechanics did that, but if the hub is the issue would it produce a noise like this after replacing rotor and pads with brand new factory pieces three times?

Your description of the noise only occurring at one point in the wheel rotation suggests a slight unevenness in the rotor surface. I will just assume that this doesn’t come from the surface of the new rotors themselves. So anything that creates a slight unevenness in the mounting of the rotor would be suspect - e.g. uneven lug nut torque or a bit of rust or other debris on the mounting surface. Over time, this unevenness will end up on the rotor surface itself.

Have the front wheel bearing inspected for wear. A worn bearing can cause a cyclic sound from the brakes.


Check the dust shield behind the rotor. Sometimes it bends and barely touches the rotor at an uneven point. That can cause the symptoms you’re describing.

Also double check the pads - a wear tab might be pushed out of alignment and squealing.

Quick update. The noise just got louder the last drive around the block. It’s now gone from a scratchy ‘pfff pff pff’ to a more metalic sound. The noise is still occuring only in one portion of the wheel. Is this a wheel bearing on it’s way out?

If the dust shield was bent it would cause the noise all the time, right or no?. I get the noise only during breaking from 30mph, anything over and I don’t hear it. I can check it if you think that’s accurate.

Okay. I’m taking it Toyota on Sunday and I’ll ask them to look.

Could it be the hub? The car was in accident a few years ago where the front tire was bent. I don’t know if they replaced the hub, but I suppose it’s possible it was damaged and is just now becoming an issue. Possible?

If I understand this correctly the uneven’ness would transfer to the rotor which would then need to be replaced or resurfaced. If that’s the case then it would just happen again. That would fit with us replacing the rotor and pad three times in less than 6k miles. If it’s lug nuts they would need be torqued to spec. If it’s the hub, then replacement. If it’s dirt or some debris sandwhiched in then it needs to be cleaned out. Would something like this affect the stopping power of the car? Something castrophic on it’s way, like the front wheel falling off? What do you think?

Not necessarily. Depending on how hard it’s pressing, higher speeds might not set up a vibration that would be as audible as at lower speeds.

And since you have to get under there to look at the wear tab position, you might as well glance at the shield.