There's two common causes of calipers dragging when new ones don't solve the problem. One is a constricted rubber flex hose and the other is brake fluid contaminated with a petroleum product. When a brake locks up, park on a slight incline, shift to neutral, and put a block about six inches downhill of one of the tires so you don't have to go chasing wildly after it! Start by loosening the steel lines at the master cylinder. If that lets the brakes release, suspect contaminated brake fluid. That's pretty serious and expensive. Also check that something isn't holding the brake pedal down a little like a misadjusted brake light switch.
If they do not release, open a bleeder screw on a caliper. If that lets it release, suspect the hose. That will always affect one front wheel first or the rear pair if they're on a single hydraulic circuit. Pedal pressure will easily force brake fluid past the restriction but the fluid won't release back to the reservoir. As the dragging brake gets hot the fluid expands. That applies the brake even harder and it gets hotter.
Thursday, March 21st, 2013 AT 1:37 AM