Sometimes the rear brakes squeal when stopping but worst sound is when releasing brakes...it is a grinding noise. Could it be the calipers?
When stopped and then releasing brakes, there is still a grind from rear brakes on 2002 Chevrolet Cavalier
it could be calipers or brake pad. seek to properly diagnose it & estimates
It could also be the rear shoes and drums as well. Less common for them to go, but does happen. I would suggest taking it to your local repair shop to have them diagnose it though.