First, I would make sure the caliper sliders are not binding and move freely. If that is okay the next part is the ABS valve/module assembly. When the brakes are locked, safely raise the front wheels and perform this test before anything cools down:
Open the bleeder screw on one locked caliper.
If fluid squirts out and the wheel immediately releases, pressure is trapped upstream.
If opening the bleeder does not release it, the caliper, pads, bracket, or wheel bearing is binding mechanically.
If both front wheels are locked and opening either bleeder releases them, loosen the front-brake outlet line at the master cylinder.
If the brakes release there, suspect insufficient master-cylinder pushrod clearance, a master-cylinder piston that is not returning fully, incorrect master cylinder, obstructed compensation ports, or a brake pedal that is not returning completely.
If they remain locked until a line at the ABS hydraulic control unit is loosened, the ABS hydraulic unit may be trapping pressure.
Pay particular attention to the brake-booster pushrod adjustment. Even a small lack of free play can cover the master cylinder’s compensation ports. As the brake fluid heats and expands, pressure builds progressively in both front brakes. After the truck cools, the pressure falls and everything appears normal again. A newly installed master cylinder does not eliminate this possibility—an incorrect part, installation problem, or pushrod set slightly too long can create exactly these symptoms.
Here is a guide that can help as well.
https://2carpros.com/articles/a-comprehensive-guide-to-fixing-automotive-brakes-locking-up/
Please let us know.
Sep 7, 2026 at 9:36 AM
