sanding has a soft backing it tends not to cut work material grinding has a hard backing it cuts or machines material
when backing up or going forward - when we turn the car we hear a grinding noise - is this likely a problem in the rear wheels with the c v joints
try scraping it off or changing the iron front!
You may very likely have bent the thin metal backing plate behind the brake rotor. That will cause the backing plate to rub against the rotor and make an awful grinding noise. Its not too hard to reform the backing plate away from the rotor.
Because the brake pads are worn and the metal backing is grinding the disc
It sounds like it could be a rust build up on the backing plate. best to have it checked out.
if screeching only when backing up, it sounds like you have a problem in reverse gear in transmission or you have a problem with loose pinion in differential
the gear box may be going out or its metal on metal rubing somewhere
The year, make and model info would be helpful but it could be rusty or bent backing plates. I doubt it is a bearing. Bearings make a rumble noise when they are going bad. Pull the rear wheels off and inspect the brakes and backing plates.
Check to see if the backing plate is rubbing against the rotor or the pads may have a hard spot in them
Backing a horse means that he has been ridden for the first time. Also called "starting" or "breaking."
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