DODGE RAM 1500 CREW CAB, V6 ENGINE. DIAL GEAR SHIFTER GOES OUT OF PARK WHILE STOPPED AND PLACED IN PARK. WILL MOVE FORWARD. I WAS STOPPED(STATIONARY), VEHICLE WAS IN PARK. ON A HIGHWAY AND THE VEHICLE MOVED FORWARD, THE STRIKING VEHICLE IN FRONT. POLICE REPORT COMPLETED, CASE #18-101657