So I had a sticking caliper on the rear of the wifes '11 limited. I went to NAPA and got 2 rear replacements. The pads and rotors were fine, so I left them. Buttoned everything back up and I'm getting a squealing sound on slow stops similar to when the pads are worn out and the squealers are hitting the rotors, but that's not the case here. There was no squealing before I replaced the calipers, only grinding from pads sticking to the rotors. I have pulled them back apart twice now and can't find anything out of the ordinary. Any ideas? Has anyone experienced this before? Short of swapping calipers again, I don't know what to do.