NHTSA Engineering Analysis EA03005

ON NOVEMBER 18, 2002, ODI OPENED A PRELIMINARY EVALUATION (PE02-086) TO EVALUATE ALLEGATIONS OF REAR AXLE TRAILING ARM FAILURES IN THE SUBJECT VEHICLES (U-VAN) WHICH INCLUDED TWO REPORTING CRASHES.ON APRIL 9, 2003, ODI UPGRADED PE02-086 TO AN ENGINEERING ANALYSIS (EA03-005) TO CONTINUE ITS EXAMINATION OF THE ISSUE. THE TRAILING ARM DESIGN IN THESE VEHICLES HAS BEEN USED IN THE U-VAN FROM MY 1997 THROUGH THE PRESENT.THE GM ANALYSIS CONCLUDED THAT THE SUBJECT TRAILING ARMS COULD CRACK OR BUCKLE IF THEY WERE DAMAGED DURING ASSEMBLY, PRE-DELIVERY HANDLING, OR SUBJECTED TO CERTAIN SERVICE RELATED ABUSE CONDITIONS SUCH AS IMPROPER TOWING OR JACKING.ANALYSIS OF ODI AND GM DATA HAS IDENTIFIED 19 INCIDENTS OF REAR AXLE TRAILING ARM FAILURES IN THE SUBJECT VEHICLES.THERE HAVE BEEN NO NEW REPORTS TO ODI OR GM IN THE LAST 12 MONTHS AND ONLY ONE NEW COMPLAINT IN THE LAST 21 MONTHS. DUE TO THE LOW COMPLAINT RATE AND THE ABSENCE OF A CONTINUING TREND IN REPORTED FAILURES, A SAFETY-RELATED DEFECT HAS NOT BEEN IDENTIFIED AT THIS TIME AND FURTHER USE OF AGENCY RESOURCES DOES NOT APPEAR TO BE WARRANTED.ACCORDINGLY, THIS INVESTIGATION IS CLOSED. THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT A SAFETY-RELATED DEFECT DOES NOT EXIST. THE AGENCY WILL TAKE FURTHER ACTION IF WARRANTED BY THE CIRCUMSTANCES. FOR ADDITIONAL INFORMATION, SEE THE ATTACHED CLOSING REPORT.