I have an 87 IROC with rear discs and I am having a strange issue. When I've been driving a while the driver's rear brake makes a grinding noise. When I come to a stop it acts like it is locking the brake on and off until I get up to 20-25 MPH. I have changed the pads and lubed everything and I can't see where there is any wear marks. I know these years had issues from what I've read but so I don't want to just replace the caliper unless I'm sure it wont happen again. Anyone have any tips?

Scott
New-IROC-Owner