OKAY A PUZZLING QUESTION HERE... PULLED OUT OF DRIVEWAY AND BRAKES JUST LOCKED UP.. ON BOTH SIDE OF FRONT BRAKES MASTER CYCLINDER or ( BRAKE CALIPER ) PUSHED INTO ROTOR... NO MOVEMENT POSSIBLE.... MAJOR RUBBING HAPPENED WHEN PULLED BACK INTO DRIVEWAY ON THE ROTOR... REPLACED PADS.. RE ADJUSTED MASTER CYCLINDER (BRAKE CALIPER)AND THOUGHT ALL WAS GOOD DID NOT EVEN GET OUT OUT DRIVEWAY AGAIN !!! STRAIGHT LOCK UP AGAIN.. ANY HELP OR IDEAS WOULD HELP.... IT MAINLY HAPPENSWHEN I AM MAKEING A SLIGHT OR HARD TURN THIS IS HAPPENING.... PLEASE HELP....[&:]

 

The Master cylinder is mounted to the firewall. It's where you add the brake fluid. It sounds like you're talking about the pistons in the calipers themselves seizing up. Inspect your brake lines for any damage, from the caliper all the way up to the master cylinder. If there's nothing obvious, you may need to replace your calipers. They aren't all that expensive and it's easy to do with the right tools. I swapped one out in the parts store parking lot during a road trip in about 30 minutes. Depending on the age of your truck, the rubber brake lines might need to be replaced due to interior deterioration, and you may need to completely flush the brake fluid out of the system.

 

My friend had the same problem on his prelude. His front calipers locked down. He got new master cylinder and brake booster. It ended up that he just needed new brake lines. Sometimes the lines turn into a one-way valve. They will let fluid in to compress the caliper, but get clogged with gunk and will not let the pressure back.
Dave