Can't see the photo. Do I understand you have the parking brake inside the rotor separate from the caliper? It sounds like the parking brake cable is sticking. This is typical for a GM or any car or truck at this age and mileage. If it were a Ford, you would have replaced three cables already!
A leaking axle seal would be the cause of the grease. That can lead to a dragging parking brake shoe and the heat you noticed. First, have a helper work the parking brake and watch that the cable releases on its own. Replace the cable if you have to pry it back.
Tuesday, March 16th, 2021 AT 10:00 AM