THIS INVESTIGATION WAS OPENED ON SEPTEMBER 27, 1999 BASED ON FIVE CONSUMER REPORTS ALLEGING THAT SOME OF THE EIGHT HITCH MOUNTING BOLTS EITHER BECAME LOOSE OR CAME COMPLETELY OUT OF ITS RETAINING PLATE.ONE OF THE COMPLAINTS INDICATED THAT WHILE TOWIG A TRAILER THE HITCH ACTUALLY SEPARATED FROM THE FRAME ON THE PASSENGER'S SIDE OF THE VEHICLE WHEN THE FOUR MOUNTING BOLTS ON THAT SIDE CAME COMPLETELY OUT. THIS ALLOWED THE HITCH AND TRAILER TO CONTACT THE ROAD SURFACE.IN ITS RESPONSE TO THE AGENCY, FORD PROVIDED INFORMATION REGARDING NINE ADDITIONAL REPORTS OF LOOSE OR MISSING BOLTS, TWO OF THOSE ALLEGING SEPARATION OF THE HITCH ON ONE SIDE.THERE WERE NO REPORTS OF VEHICLE CRSHES, INJURIES, OR A COMPLETE SEPARATION OF A HITCH ASSEMBLY.SCOPE:1997 THROURGH 2000 MODEL YEAR EXPEDITIONS AND 1998 THROUGH 2000 MODEL YEAR NAVIGATORS BUILT AT MICHIGAN TRUCH ASSEMBLLY PLANT FROM JULY 22,1 996 THROUGH DECEMBER 9, 1999.DEFECT: LOSS OF CLAMPING LOAD OF HITCH ATTACHMENT BOLTS.REMEDY:THE HITCH MOUNTING BOLTS AND NUT PLATES WILL BE REPLACE WITH HIGHER STRENGTH BOLTS AND PLATES.ADDITIONALLY , THE TORQUE VALUE FOR THE MOUNTING BOLTS WILL BE INCREASED AND AN ADHESIVE WILL BE ADDED TO THE BOLTS.