THIS EA WAS OPENED BASED ON A RESPONSE RECEIVED FROM FORD MOTOR COMPANY TO AN INFORMATION REQUEST (IR) SUBMITTED DURING SQ00-018.FORD STATED IN AN INTERNAL SERVICE MESSAGE THAT IT HAD CHANGED THE STEERING GEAR SECTOR SHAFTS AND PITMAN ARMS INSTALLED 1999 MODEL YEAR F-SERIES SUPER DUTY VEHICLES ON MARCH 22, 1999.FORD STATED THAT THESE DESIGN CHANGES WERE IMPLEMENTED TO MAKE IMPROVEMENTS IN VEHICLE STEERING AND HANDLING, AND THAT VIRTUALLY ALL OF THE REPORTED FRACTURED SECTOR SHAFTS WERE THE RESULT OF EXTRAORDINARY, POSSIBLY MULTIPLE, IMPACTS.AN ENGINEERING ANALYSIS CLOSING REPORT IS ATTACHED.