Driving home had both rear brakes start dragging or sticking. Replaced brackets guide pins and brake pads.. No leaks in the system, both calipers depressed easily. Noticed that after short ime frame. Brakes are free but start dragging again as soon as you depress the brake pedal. Any ideas?

 

If both are not releasing I would suspect the brake hose from the center of the rear axle to frame is bad. They can collapse internally and hold pressure.