Wheel bearing noise?

Question

Apologies in advance if this question has been asked before; I'm not familiar enough with cars to identify or make speculations on the relative source of this problem.

CAR DETAILS:

• 1999 Toyota Avalon XLS

THE PROBLEM:

There is a grinding, tinny sound coming from my wheel on the rear right-hand side.

I have been driving around regularly and my car was not making this sound until only recently. Except for a bumpy road (small potholes, dips, bumps) I take on a normal basis, I have not had anything serious happen while I was driving.

This sound can be heard when I drive at low speeds (10-20 mph). It can also be heard consistently as I drive and no matter how fast I drive, although it seems to intensify if I speed up and fade away when I make turns.

See the video below for a demonstration: (headphones users - caution!)

http://youtu.be/MMhsIckC4kQ

Some things I know:

1. My tires are somewhat under pressure, but that should not be what's causing the sound.

2. The brake caliper in the right rear wheel seems to be in place and not loose.

3. I drive on a rather bumpy road regularly, so the problem may be related to the suspension system.

Does anyone have any insight on:

1. The source and reason for the sound

2. Possible ways to fix the problem

3. A possible range of expenses to fix the problem

Any help and insight would be appreciated! I'm not particular familiar with auto parts and mechanics, so simple-worded explanations would be nice :)

Thanks!

Answer 1

Jack the back of the car up, and spin the wheels by hand - comparing the two sides so you can tell what's different on the bad side.

Try to shake the wheel vertically and horizontally - a worn wheel bearing will have more play in it than a good one. When spinning the wheel without load, a worn wheel bearing will make a slight rumbling sound, and might seem slightly lumpy (if it does, it's REALLY worn!)

I suspect, however, that your sound is more likely to be worn brakes. Inspect all four pads on the rear axle (you may have to remove the wheels to see them clearly) - most likely one or both on the noisy side will be worn right down. If so, replace all four.

If the brake pads on one side are worn significantly more than the other, get the caliper and parking brake inspected as well - one or other might be sticking and causing more wear. If when you try to spin the wheel, it's much harder to turn than the other side, then this is almost certainly the problem.

Answer 2

It sounds like the brake pad scraper. The metal thing on the brake pad that tell you that your brake pads are too thin. Judging from what I heard It sounded like metal on metal. I would take a look at your brake pads and rotors as well.