I WAS APPROXIMATELY 8 OR 9 CAR LENGTHS FROM A VEHICLE THAT SLAMMED ON HER BRAKES BEFORE HITTING THE CAR IN FRONT OF HER, SO I STOOD UP ON MY BRAKES AT ABOUT 30 -35 MPH. THE CARS BRAKES DID NOT GRAB FOR ABOUT A SECOND, THEN STARTED TO GRAB RIGHT BEFORE IMPACTING THE CAR IN FRONT OF ME. *JS