Why did I think this would be easy, it never is🤦‍♂️

This should have been a run of the mill rotors + pads job. Replaced all 4 wheels, followed manufacturers instructions too the tee. Lubed everything, fully compressed the pistons, torqued all to spec, bled the brakes, everything added up.

Last night was the first drive out, and it felt weird, but I expected it to. New rotors, pads, put my winter tires on, and it was extremely cold for what's usual. I broke the brakes in and figured they just needed a bit of time.

Come today, I drove a few miles and noticed I didn't roll very easily. Got home, checked the rotors, and both the rear ones looked like this:



Obviously I was immediately worries, the brakes had been rubbing only the outer portion to death.
Took a look at the pads themselves, and they've worn down a bit already and are sitting uneven:
(Notice the gap towards the middle right?)

It's a mess. I went back and re compressed the pistons, still the calliper is too tight. Can't get the wheels to even spin.

I've nearly run out of ideas lol. Whenever I've been in a pickle this group has pulled me out via a link to an article, or a special tool, or just pointing out something I've stupidly overlooked, so as always, any help, recommendations, or ideas are extremely welcomed. Thanks y'all 🤝🏼

 

What tool did you use to compress the rear pistons?

 

A disk brake caliper tool set I rented from O'Reilly's

 

The kind that turns the piston as it compresses? I assume so, since I don't think you'd get it in otherwise. That's the only trick I know for the rear brakes.

​​​​Maybe someone smarter than me will come along.

 

I also assume you've checked to make sure the parking brake isn't on.

 

Haha yes, I've had some daft moments but I didn't mess up that bad😂

 

Did you lubricate the pad sliding surfaces?

 

Looks like the pad is cocked in the bracket. The bracket should be cleaned with a wire brush where the pads slot in, and the pad ears should be lubed and able to move freely in the bracket. If the pads are tight in the bracket, all sorts of weird issues can pop up. The pad mounting shims should be tight in the bracket, but the pads should be slightly loose in the mounting shims. I’ve even left those mounting shims out at times to make sure the pad was loose enough in the bracket.

 

Yep. That's my theory too.

 

That's not a bad idea, but I've already done all that.
I used wire brush, sand paper, brake cleaner, and rubbing alcohol on all all the calipers, and caliper brackets because I painted them red since I had them off (I used caliper paint and taped off the pins and pistons before painting so that shouldn't be an issue)

The kit that i purchased came with pad brackets all around, but the rear brackets were mishaped and didn't fit so i just reused the originals after cleaning them well. Greased all the inside of brackets/ears of pads too.

I'll go double check on their freeness to move, even try taking them out, but all seemed solid when i first installed 🤷‍♂️ will report back with any updates soon

 

Well, just took of the back brackets, put the pads in, reattached the callipers, made sure the rotors could spin, turned the car on, pushed the brakes in, let off, and they are stuck again. The pistons just won't let up. At this point i feel like my calipers have both gone bad, but i don't know how that could even be possible at the same time.

 

I hear one of two things taking place...

(1) Since you are only pumping the brakes in the garage, I would not expect the caliper to unload after pressing the pedal. They aren't designed to self-release like that.

(2) How hard is it to slide the pads into the bracket shims? They should slide around in there pretty easily, and the shims providing just a little bit of resistance to prevent squealing. If the pads require too much force to slide into place, they won't release correctly, or they will get crooked and not contact the rotor squarely.

 

Oh? I was under the impression that when I let off the brakes, the release of pressure should cause the caliper pressure to release too. Am I incorrect there? How should I see to it that the calliper releases then?

As far as pads, they move extremely easy in there. My last test i removed the bracket all together and the brakes still locked up.

 

Would damage to the caliper piston boot cause it to not release pressure?

 

My understanding is that when you are releasing the pressure you may not actually visibly see it in the caliper, as in it won't retract and leave a visible gap, it just won't be putting force on the pad. I do believe that if you have a damaged boot, junk can get in there and score the piston making it less free to move in and out (possibly) Eventually scoring it enough could cause a leak in the seal.

 

As mentioned above, the piston will not visibly retract when you release the brake pedal. The spinning of the rotor will move the pads a hair away from the rotor and push the piston back just enough to create that tiny gap.
If you recall, you had to push the pistons in to install pads and you cannot just do it with your fingers. You needed a caliper piston tool to retract it.
If dirt got behind the dust seal then yes it could cause the force needed to retract it to increase. The damage would need to be severe to fully lock the brakes though.
Does the pedal feel normal?