I WAS GOING ABOUT 25 MPH WHEN THE TRUCK AHEAD OF ME STOPPED. I HIT THE BRAKE PEDAL HARD AND THE BRAKE PEDAL SEEMED HARD AS IF IT WASN'T MOVING AND MY CAR JUST KEPT MOVING FORWARD RESULTING IN REAR ENDING THE TRUCK AHEAD OF ME. I CHECKED THE BRAKE FLUID LEVEL AFTER THE CAR WAS TOWED HOME AND THE FLUID LEVEL LOOKED OKAY MAYBE DOWN A LITTLE. HAVE NEVER CHANGED OUT THE BRAKE FLUID AND HAD THE BRAKES RECENTLY CHECKED BY LEW SCWAB TIRES BRAKES NEW BRAKE SHOES FRONT AND REAR BRAKES OKAY