I DRIVE A LOT DUE TO COMMUTING TO AND FROM WORK. RECENTLY I HAVE HAD TO BRAKE SUDDENLY DUE TO RAPID CHANGE IN FLOW OF TRAFFIC. I HAD A NEAR MISS. I WAS 5 CAR LENGTHS BEHIND A VEHICLE IN FRONT OF ME WHEN TRAFFIC CAME TO A HALT. I WAS TRAVELLING AT 55MPH. I HAD STEPPED ON THE BRAKE AS FAR DOWN AND HARD AS I COULD. MY VEHICLE WOULDN'T STOP. I HAD TO SWERVE AROUND THE VEHICLE IN FRONT OF ME IN ORDER TO AVOID HITTING THEM. MY SEAT BELT DIDN'T LOCK AND I FELT AS IF I WASN'T SLOWING DOWN. THE SAME THING HAPPENED TO ME WHILE DRIVING AT A SLOWER SPEED OF 30 MPH. I BROKE AGAIN HARD AND MY CAR WOULDN'T STOP.