Brake grinding, sounding like pad backing plate contacting the disk. Started suddenly at all four wheels after descending a hill. Been going on for several weeks now, but zero disc damage, no grooves or evidence of friction welding. Now, it has settled on the right, rear brake. Rear brakes - calipers and pads - replaced two years ago, 15,000 miles since then, 10,000 of those miles were two cross country highway trips hardly using the brakes. The sound can be heard at random times. It grinds when the brakes are ambient (22F), when they are hot, when first braking, when at the end of braking. It’s not constant, entirely random. A friend says that it may be the ABS, but the frequency seems way above what the ABS would do. Maybe a piece of gravel stuck somewhere. Any thoughts?

 

Things that make you go..."Hmmmmm?" rubbing your chin in your hand...

In a nut shell, a good cleaning wouldn't hurt...

I would pull the wheels and check the calipers, maybe pulling the pads to inspect and using either anti-seize or copper grease to re-lube the pad backing plates and the sliding parts. (NOT on the Pad surface or Rotor surface).

I would also check the Parking Brake Cables, ensuring they are releasing correctly and not causing a dragging effect.

Best of luck...

Motor on!

 

I just had the same type issue. I pulled my rear wheels and pads and found the bottom portion of the pad was worn down to the metal and the tops still had about 35% left. I determined that it was from me using my emergency brake to slow the car down when I did not want to have my brake lights come on (don't ask, )

 

Thanks, guys. I also use the hand brake to trim speed when I'm moving, maybe a touch fast, and see an officer of the Law nearby. Methinks that a good cleaning is the way to go. I pay my car insurance by the mile so my car sits for days at at time when I'm biking or scootering. In feeling the discs the inner and outer rust ridge is quite tall, so I think that when the brakes are applied the pads press into the rust mountain and grinding sounds result. I'll knock that off too.

 

That's exactly what I do/did. Check your rear pads, I had to pull mine off to see the bottom wear.

 

Were you dragging the brakes going down the hill? Could have overheated the brakes and cracked the pads or something.

 

Tried some stops with the ebrake and no grinding resulted. Hmm. In coasting down the hill I hit the brakes, not hard for a moment, then coasted up to speed again, braked again so there was time to cool between uses. I got in the habit of not coasting down hills in gear because with another car I had the high vacuum would cause an injector to temporarily stop working. On this hill it is too steep for 5th and 4th and in 3rd it just revs too high for my tastes. It looks like a disassembly and thorough cleaning and inspection is in order, but that has to wait till my pal gets his heated garage cleared out. I hate working out in the street in the winter.