Nissan Repair: FRONT BRAKES, 4x4 nissan, vacuum booster

Question
MY SON HAS A 97 4X4 NISSAN PICK UP, HIS FRONT  BRAKES ARE GRADUALLY LOCKING UP THE LONGER YOU DRIVE THE TIGHTER THEY GET THE BRAKES START TO BURN HE HAS TO PULL OVER AND WAIT TILL THEY COOL DOWN. I'V CHANGED THE CALIPERS,BRAKES AND BLEED THE LINES. STILL HAVE THE SAME PROBLEM. WHAT ELSE CAN I DO.

Answer
Rich,

Either the new calipers are sticking or the actuator rod in the vacuum booster is turned too tight.  The rod is adjustable and if it is too long it will gradually apply until the brakes drag and lock up.  Need to remove the master cylinder, do not remove the brake lines, just remove the two nuts and pull the master cylinder forward until you can see the rod that sticks into the back of the master cylinder.  Get a wrehcn adn some vice grips and turn the end of the rod in.  It is adjustable.  Only go a half turn at a time.  Drive it and see when the brakes stop locking up and you are done.  It takes a couple of times.  But, if you tighten, shorten, the rod, too much it will cause the brakes to be loose and that is just as bad.  So, a half turn at a time and put it back together and try it.  Email me back if you have further questions.