I replaced all 4 brake rotors and pads on my mom's '02 trailblazer. After getting everything back together and going for a test drive, the driver rear brake area is making a rubbing noise which is very rhythmic and constant at low speed. When turning it gets worse, and at 40+mph going straight it seems to go away. Thought it could be a faulty rotor so replaced it to find out that was not the problem. Nothing is smoking or anything and the car pulls itself at idle, so I don't believe it's the caliper either...I would assume a sticky caliper would have a more constant grind rather than a rhythmic rub anyway. Please help! Thanks!