What does a bad wheel bearing sound like?

[Marty Rogan]

I suspect that I may have a wheel bearing going out on me. There is a noise coming from the right rear. It sounds like a flat spot on a tire. Doubt it is that because the tires are nearly new. It is kind of a thunk-thunk thunk sound. The noise speeds up with faster tire rotation. The car only has 78K original miles. I am a little surprised if it is a bad wheel bearing.

I checked the brakes, which looked fine. I even had the drum turned in caseit was warped, but it didn't help.

Anything else I can check to confirm a bad wheel bearing? Could it be something else?

TIA,

Marty

[Brandy]

My 4Runner had the similar sounds, plus it would make the steering wheel shimmy. I had delayed in having the tires balanced. Perhaps it hopefully is something as simple as that.

[240ZX]

Marty,

A wheel bearing going out, has kind of like a squeaking (as it rotates) sound.

[Marty Rogan]

This is on the right rear, so I don't get the shakes in the steering wheel. Good thought though. I do have a very slight vibration, so I'll have the balance checked.

It definitely isn't a squeek. More like a thunk or thump. It's not U-joints, as that is a different sound and I have fixed those already.

Marty

[jmortensen]

IME wheel bearings make more of a growling noise which changes with load. You can usually identify a bearing noise by swerving side to side. If the noise changes pitch or goes away while swerving, then it's a wheel bearing. Thunk or a thump huh? If it changes with vehicle speed then my first thought would be a U joint, but you say you just fixed those...

[mlc240z]

i agree with jmortensen, in my experience, it's always been a 'growl' or moan that can change with speed and/or disappear with changes in direction.

definite thump that matches speed could be a separated steel belt (defect) even on new tires.

try swapping tires to see if the sound follows the tire, this would indicate a bad/defective tire. unfortunately, new doesn't always mean good.

[kinfish]

The right rear outer bearing went bad on my '71 240 at 175K. I would describe the noise as a constant howling that increased in amplitude as you increased speed. It was really annoying. The only way I could identify the source was by removing the axle shaft from the hub and spinning the wheel. Noticeable differance between left and right. I pulled the right side apart and found the outer bearing noisy and the inner OK. Replaced both bearings and no noise. Not an easy job ...... take your time.

[Marty Rogan]

Thanks. I'll try swapping tires and go for a ride.

Marty

[Marty Rogan]

Ok. I swapped the wheels on the right side. The sound seems to have been reduced dramatically. I can't say that it is gone completely. It seems more like a very low rumble now. Maybe that is just normal totational noise?

I was expecting it to shimmy on the highway, but it was perfectly smooth at 70 mph.

I guess I will get that wheel balanced and have them check the belts on it.

Marty

[dogma420]

I'd say the belts are seperating, and they're seperating slightly on the wheel you put on...it causes a 'bump' in the roundness on the tires...I thought the same thing on my Dodge Van (but with a solid axle)...turns out my 5,000 mile tires had come apart--got a new replacement no charge--at Les Schwab--a good tire place in the Pacific NW.

Make sure when you take the wheels in that you specifically tell them you think the belt is seperating--the balance machine doesn't really notice it--its more of a roll it on the ground type test--you can do it yourself.