THE SECOND INCIDENT ON SEPTEMBER 1, 2018: 2016 GMC SIERRA 1500 Z71 4X4 CC I WAS SPEEDING UP TO MERGE ONTO A BUSY HIGHWAY IN DENVER, HEADED TO THE MOUNTAINS TO TAKE MY WIFE AND THREE BOYS CAMPING. A CAR IN FRONT OF US HAD BEGAN SLOWING DOWN, SO I BEGAN SLOWING DOWN, THEY SLAMMED ON THEIR BRAKES, SO I SLAMMED ON MINE. THE ONLY DIFFERENCE BETWEEN OUR VEHICLES BESIDES SIZE WAS THAT THEY CAME TO A COMPLETE STOP, AS SOON AS I SLAMMED ON MY BRAKES, THE TRUCK JUST GLIDED ON THE PAVEMENT AS IF IT WERE A SHEET OF ICE. THE ONLY THING TO STOP US WAS THE BACK OF THEIR VEHICLE! WE GOT A RENTAL TRUCK AND CARRIED ON WITH OUR CAMPING TRIP. AS WE DROVE PAST THE ACCIDENT SCENE SLOWLY HOURS LATER TO HEAD BACK TOWARDS THE MOUNTAINS, (TRAFFIC WAS MUCH LIGHTER) WE NOTICED THAT THE SKID MARKS FROM MY TRUCK WERE STRAIGHT WITH NO BREAKS IN THE SKID LINES, WHICH TO MY KNOWLEDGE INDICATES THAT THE ABS SYSTEM WAS NOT WORKING PROPERLY. I NEVER HAD ANY INDICATOR LIGHTS SHOW UP ON THE DASH. AFTER THAT ACCIDENT, MY WIFE AND I CONDUCTED A LOT OF RESEARCH, COME TO FIND OUT THAT GM TRUCKS HAD MULTIPLE COMPLAINTS WITH THEIR BRAKES, WISH I HAD DONE MY RESEARCH FIRST.