Originally Posted by benjamming
Yep, passenger side forward shoe had completely delaminated & the trailing shoe crumbled. Replaced both sides. Passenger pad had also completely worn down. Caliper frozen. Heat buildup on passenger side rear was quite a lot.
Both rear wheels in air. Adjuster completely loosened such that rotor can be removed with parking brake applied. Parking brake off & still can't turn the rear wheels freely unless ~ 100-150 ft-lbf torque applied.
It's either the parking brakes or the calipers. You have to narrow it down. Try pulling a wheel off, remove the caliper, put the wheel back on. If it spins freely it's the caliper. If it's still stuck its the parking brake.