Diagnosing a weird intermittent bearing/brake noise

philipguziec · 08-24-2004, 12:35 PM

My car recently started making a weird noise from the passenger front wheel somewhere. It was kind of a low pitch squeek at wheel speed that lasted for about 3/4 of a revolution. Touching the brakes would make the noise go away but it would immediately return when the brakes were released. It would happen more when hot and turning the car to unload/load the wheel would reduce/increase the noise respectively. It was loud enough that I could feel it in the floorboards.

I was afraid I was going to mess up a hub so I stopped driving the car for a week while I waited for the mechanic to get to it. When I drove the car to him, it was barely making the noise. He drove the car a whole bunch to get the car hot and he couldn't repeat the noise.

Any idea what it might be/was? The noise was mildly annoying but, more importantly, I'm worried about siezing a bearing and messing up a hub or suspension component.

Thanks,
Phil

Rot 911 · 08-24-2004, 12:44 PM

Phil, wheel bearings are tough. You will hear a lot more than an occasional squeal before one goes. Actually a bad wheel bearing tends to be more of a rumble than a squeal. I suspect it is just a brake pad squealing. Brake pads are cheap and you can replace a set yourself in about 15 minutes. Change the fronts out and see if the squeal goes away.

zbph10 · 08-24-2004, 02:17 PM

My bad front wheel bearing made an intermittent low rumbling noise usually when I was making right hand turns.

I jacked the car up and spun both front tires, one was nice and quiet, the other was growling back at me.

Sounds like you may have a brake problem

That's my limited experience, good luck

Brian

cowtown · 08-24-2004, 02:53 PM

It's possible that your brake caliper pistons aren't fully retracting sometimes, letting the pad glide against the rotor and squeak. When you push the brakes, it stops because the pad is in full contact.

braddb_82SC · 08-24-2004, 03:13 PM

My brakes have squealed similarly to yours for going on nine years now. As soon as I tap the brakes the squealing stops. In those nine years have rebuilt each caliper twice, the rotors once, the flexible brake lines once, the bearings once and the pads many times (including pad brand changes). My mechanic checked the brakes and could find nothing wrong. Luckily the sound is intermittent. I just consider the noise a car idiosyncrasy.

Maybe I'll try a new master cylinder next.

-Brad

juanbenae · juanbenae's Garage

i agree with colin. mine did the same thing until i rebuilt the calipers. same wheel even...

philipguziec · 08-24-2004, 08:44 PM

Thanks all. I won't sweat the noise.

Phil

JohnH · JohnH's Garage

I found this thread after doing a search on "brake noise." I am also experiencing a rotational noise from the front that can be felt through the steering wheel. It presents as a low-pitched "wooooo, wooooo, wooooo..." when rolling slowly and a higher-pitched "woo,woo,woo..." when going faster. It doesn't do it when cold, or wet, but it's a daily experience after I've driven a few miles unless it's raining. The lighest touch on the brake pedal makes the noise stop, but it always returns. I've replaced pads and wheel bearings, and the calipers have been rebuilt. My mechanic beveled the front and rear edges of the pads and applied copper anti-seize to the back of the pads. That made the noise stop for about a week and I was about to declare victory. But now its back and most ANNOYING! Do any of you have any further suggestions?
Thanks,
John

philipguziec · 11-19-2004, 09:13 AM

That's EXACTLY what I've got going on. It's intermittent, and I just don't worry about it. It can get annoying, though.

johnrix · 12-04-2004, 06:18 AM

I too am experiencing some similar problems, only mine was making some horrible noises. I tried to take the rotor off last night, but can't seem to get it to come off.

After you remove the nut and the washer, is the rotor supposed to just easily slide off?

cowtown · 12-04-2004, 07:47 AM

Quote:

Originally posted by johnrix
I too am experiencing some similar problems, only mine was making some horrible noises. I tried to take the rotor off last night, but can't seem to get it to come off.

After you remove the nut and the washer, is the rotor supposed to just easily slide off?

If the brake caliper has already been unbolted and swung out of the way, then the horseshoe-shaped clamping nut and washer under it are the only things keeping the hub on. The whole hub and rotor come straight off the spindle as an assembly.

gsxrken · gsxrken's Garage

The master cylinder could be leaving just a little bit of pressure on the system, causing a pad to drag. Or a rubber brake hose is swollen nearly shut inside, so that it applies pressure but doesn't let it relieve too easily. The 3 lines on the car are an easy, cheap, and probably represent a saftey improvement over your probably-still-stock rubber lines.

johnrix · 12-04-2004, 11:16 AM

Well, the brakes may very well be contributing to the noise, but it looks to be more serious. I just removed the rotor, and the inside bearing has begun to come apart! Now I just have to figure out how to decide what is what. Seems to me that some of the bearing is missing.

cowtown · 12-04-2004, 12:55 PM

If the aluminum hub's OK, you should be able to get a new set of bearings and races, and have a machine shop press the old ones out and pop the new ones in. The parts are not very expensive. I'd probably think about doing both right and left hubs, assuming they both have the same miles on them.

Good luck. Let us know how it turns out.

johnrix · 12-04-2004, 01:30 PM

I think the inner race is stuck on the spindle, so I guess I don't have to worry about having it pressed out of the hub. Just have to figure out how to get it off the spindle, since it is stuck on there. I'm off to Harbor Tools to get a puller and try that first.