Grinding sound

[justin0469]

As I am driving I can hear a rubbing sound as the wheels rotate under acceleration or deceleration. It stops or gets more quiet if i firmly press the brakes. It is not a constant sound, just about once per rotation. I looked to see if anything was in the way of any of the wheels rotating but couldn't see anything. When I jack up the car and spin the wheels, I don't hear anything. Any ideas?

 

[zippyshoe]

This sound could be caused by worn brake pads. Many brake pads are designed to intentionally create a metallic scraping sound when the brake lining on the pad wears below a certain thickness. Checking the brake pads may be a good place to start.

 

[justin0469]

Hmmm, if it is brake pads, thats the last time I'm buying Duralast from autozone. I replaced them not all that long ago. And I thought that metal tab constantly drags on the rotor, not just once per revolution.

 

[zippyshoe]

There are other issues that could also cause a grinding sound besides brake pads - if a brake caliper is not releasing properly, for example. However, worn brake pads is probably the most common cause as well as one of the simpler problems to check/correct.

 

[justin0469]

But wouldn't that still be a constant dragging sound still? I'll still check it out though.

 

[1g_tsi_awd]

Sometimes brake pads gouge brake calipers and that's what it could be, it happened to me on my saturn... Hahaha...

 

[justin0469]

What do you mean pads gouge the caliper?

 

[zippyshoe]

But wouldn't that still be a constant dragging sound still? I'll still check it out though.

Worn brake pads can produce a pulsating sound - its happened to me before. If your rotors have even a slight warpage, the part of the brake pad that makes contact with the rotor may only contact the "high" spot of the rotor. Hence, the sound will pulsate once for each rotation of the wheel.