You won't see this on newer pads but on older, pretty worn pads. They will wear at an angle within the caliper. When they do that to an extreme like mine were, they no longer glide smoothly on the 2 pins. Brake pedal pressure can easily force the pads closed onto the rotor but they don't completely release due to binding on the pins.
This only applies to the pad type that has the 2 pins going through them.
A simple fix for this would be to actually swap the inner with the outer when maybe about 40% worn. It would add life to the pads too since they will wear more evenly throughout the whole pad surface.
In my case with the dragging RF caliper, the fix was just another set of pads. The pins show some of the binding wear but they are still fine.

 

Super thread. I have a much less serious problem: a pull to the left when braking. That generally means the right front caliper is an issue, correct? Means it is dragging or otherwise not able to apply as much brake force as the left? Or is it the other way around and the left is dragging, therefore the pads are closer to the rotor, so the left essentially brakes first? Guess I should pull the pads and look-see.

 

Update to my sitcheeashun. Problem is flexible hose on the left side. It is not allowing complete retraction of the pads, so the left side brakes sooner than the right. Another problem is finding that part. Autozone part is too short. No lift on the truck either. Stealer wants $25 per hose. Think I'll run over to Pepboys.

 

I have a 98 4Runner. Both front brakes locked up. I've replaced the M/C, Flex hoses, calipers, pads, and front rotors. Today my son drove it through mud to pull his friend out and when he made it back to the blacktop the right front was pulling. When he backed up the caliper released and is now working fine. Any Ideas?