GX470 puzzeling rear brake issue

[OKHondo]

I have owned my GX for about a year now, and soon after I purchased the rear drivers side brakes began squeaking. They only squeak when letting off the brake pedal. It makes the sound like the pad is dragging/contacting the rotor and not fully releasing. I went ahead and pulled the drivers rear wheel off and noticed that it was missing one of the brake pad clips. Pulled caliper and reinstalled new clip and made sure the caliper wasn't froze by using a C clamp. All seemed in great working order. Squeaks were gone for a about a week. Finally decided about a month ago to just replace all rear hardware, including rotors and pads new pins and boots. Wire wheeled all the rust off caliper bracket, mounting surfaces, lubricated, etc... Brakes were perfect for 3 weeks. Squeak started coming back last week and looked into it again, only to find that the brake pad clip looks like it has been ground off on the side facing the rotor and was able to pull it out by hand without dissassembly. Again the squeak only happens after releasing the brake pedal and continous thereafter. No pulsing, shuddering, and the vehicle brakes straight. This one has me scratching my head. I could use a fresh set of eyes from someone who understands these vehicles better than me. Awesome vehicle, but this squeaking has to go. Thanks for the help!

 

[GXO]

Sounds like rusted slide pins or a stuck piston

 

[little_joe]

Got a picture of one of the rear calipers? And are you certain the anti-rattle clip is installed properly?

I'd say it's practically impossible for something to be jamming the clip into the rotor, since it's recessed and stationary - hence the question about install. Are you positive it's the clip squeaking, and not the dust cover or parking brake?

Just because you worked the piston with a clamp doesn't mean it's working fully, BTDT. But that likely wouldn't account for the pin anyway.

 

[OKHondo]

I messed with it again last night and should have taken a few pics. I worked the piston back and forth and it definitely feels smooth and not hung. I purchased new slide pins and boots already last time, but noticed last night that they didn't feel as smooth as I'd like. They are better now and am curious if rubber on the bottom boot wasn't bound a little bit. It's much better now and put a clip back in it. The most interesting find I think, is that the brake fluid tank was overfilled. I'm not sure if/when I had the oil last change they decided to top it off for me or what, but there definitely wasn't any room left for any fluid expansion. I bled the brakes and pulled fluid down to normal level. Quiet this morning on the way to work, hopefully it lasts this time. Still doesn't explain the clip, unless I just totally missed putting that clip in backwards. We shall see.