My camry ('95 V6) has turned into one of those annoying cars that squeaks whenever it's rolling. This is especially apparent when driving at low speeds. It does this without me touching the brakes at all. It also squeaks when I brake, but it has always done that and that's not nearly as annoying. It may have something to do with the new rear rotor that I just got, after the old one seized up. That's when the constant non-braking squeaking started. I have already taken the car to a mechanic, who says the brakes are working fine and didn't fix the squeak. Anybody know what this is?

Possibly a bad joint, CV most likely in this case. Also, you'll probably want to try either removing the shims on the front brake pads, and either replacing them, or just running with them off for now. I used to have the same annoying squeaking in my 99 that no one could figure out, and I was messing around with the brakes one day, took the shims off and ran the car without them, and the squeak was gone.