Chevrolet Repair: BRAKES, flex hoses, wheel locks

Question
THIS IS FOR A 78' CHEVY PICK UP.  ON A WET STREET IF I HIT THE BRAKES HARD THE DRIVERS SIDE FRONT WHEEL LOCKS UP BUT THE PASSENGER SIDE DOESN'T SEEM TO BE  GRABBING. IS THIS A WHEEL CYLINDER OR SOME OTHER PROBLEM.

Answer
I would bet the flex hoses from the frame to the wheel. One of them is restricted at the metal sleeve where the clip holds it on the steering knuckle.
Try bleeding them, and fluid will be much slower on one side, or not even flow.
If that's what you find, just replace them both, cause the other will do it before too long, and considering the trust you have in that particular safety system, the cost of those hoses is cheap.
Van