OWNER REPORTS THAT BALL SOCKET ON DRAG LINK SEPARATED CREATING A LOSS OF STEERING. VEHICLE DEPARTED RIGHT SIDE OF ROADWAY AND CAME TO REST IN A SWAMP. OWNER REPORTS VEHICLE MILEAGE AT JUST OVER 501,000. ROUTINE INSPECTS FAILED TO REVEAL ANY INDICATION OF IMPENDING FAILURE. THIS BALL SOCKET WAS NOT SUBJECT OF RECALL *CB