WHILE DRIVING AT 55 MPH, I APPLIED THE BRAKES TO COME TO A STOP. THE BRAKES BEGAN TO SLOW THE TRUCK THEN THE PEDAL WENT CLEAR TO THE FLOOR AND ALL BRAKING ACTION WAS LOST. THIS CAUSED ME TO STRIKE THE VEHICLE IN FRONT OF ME. AFTERWARDS I OBSERVED BRAKE FLUID DRIPPING FROM THE LINES FORWARD OF THE REAR AXLE AND NEAR THE FIREWALL AREA. I WAS VERY LUCKY TO ESCAPE INJURY TO MYSELF AND THE OTHER DRIVER THAT I STRUCK. MY TRUCK SUSTAINED EXTENSIVE DAMAGE TO THE FRONT END. I HAVE NOT GOTTEN ESTIMATES FOR REPAIRS YET. *TR