WHILE DRIVING @60MPH THE UPPER A ARM PIVOT BOLT ON THE PASSENGER SIDE BROKE WHILE SLOWING DOWN THIS CAUSED A SUDDEN PULL TO THE RIGHT FOLLOWED BY A UNCONTROLLABLE HARD PULL TO THE LEFT WHICH PUT MY TRUCK IN THE CENTER OF THE DIVIDED HIWAY.....IT WAS IMPOSSIBLE TO MOVE THE TRUCK AT MORE THAN 15 MPH AND STILL HAVE CONTROL. AS THIS PART CANNOT BE INSPECTED WITHOUT REMOVAL OF CRITICAL ALIGNMENT CAMS AND COMPRESSION OF THE COIL SPRINGS IT IS NOT SOMETHING ANY SUSPENSION WILL NOTICE. I HAVE DROVE THIS TRUCK FOR OVER 170,000 MILES AND IT HAS RETURNED TO THE DEALER FOR SERVICE AS OF THIS MORNING THERE WERE NO WARNING SIGNS AS IT DROVE STRAIGHT WITH NO PULL TO EITHER SIDE AND NO WANDERING. AS IT HAD NO PROBLEMS OR WARNINGS I FIND THIS VERY ALARMING AND AM THANKFULL THAT THE ROAD THAT I WAS ON AT FAILURE TIME WAS DIVIDED.......VEHICAL IS AVAL. FOR INSPECTION.....THANKS STEVE HANSON