I was asked to work on the brakes on an '06 Pontiac G6, right rear brake pad had gone metal to metal. I bought rotors and pads for both sides, driver side was good, fairly even wear, lots of pad left, but the passenger side was indeed, metal to metal. On disassembly,I found something I'd not seen before..... The outside pad was worn completely out, the inboard pad (against the piston)was virtually untouched. Also, the Piston was stuck, it was very hard to push it back into the caliper (c-clamp) to clear the new pads. The parking brake actuator appeared to be free and not hung up. I'm ordering new caliper assys to replace at least that caliper, but why would only the outboard pad be worn out? The wheel turned freely when I started taking it apart, so it wasn't jammed, at least then. Ideas?? Thanks! AlanP

  • Welcome to Motor Vehicle Maintenance & Repair! As a guess, I'd be looking at if the caliper is sliding correctly. Check for corrosion and bent slide pins (if so equipped). You are looking for anything which would keep it from sliding. Replacing the caliper is a good idea, because more than likely it's been stressed due to the heat buildup. Commented Jan 12, 2020 at 4:55
  • Thank you for the reply! That's what I'm going to do, replace the whole thing, probably both sides, then start on the fronts....AlanP
    – AlanP
    Commented Jan 13, 2020 at 5:10

1 Answer 1


A typical brake assembly has a single or double piston on one side, when the brake pedal is depressed the piston pushes the pad into the rotor, and pushes the assembly, including the caliper, in the opposite direction. The caliper slides on pins, allowing even force to be applied on both sides of the rotor.

Disk brake assembly

It sounds like the caliper seized, keeping the outer pad in contact with the rotor, this caused the outer pad to wear out. It also sounds like the piston seized as well, which means this assembly is toast and needs to be replaced. I'd bet money the other side is also in poor shape, it's always good to replace both sides.

Constant contact on the pad would have caused heat, and could have cooked the brake fluid, so that brake should be bled thoroughly. It's worth checking the hose too to ensure there was no damage. The heat could possibly have damaged the wheel bearings or broken down the grease, but that's less likely.

  • Thank you! The only thing I found that appeared to be stuck, was the piston, which is why I couldn't understand why the OUTER pad was trashed, but not The inner. But yes, I'm replacing the calipers, both of them and I'll be bleeding a lot out when I do that. Man, I appreciate taking the time to reply....
    – AlanP
    Commented Jan 13, 2020 at 5:05

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .