THE ALLEGED DEFECT INVOLVED ENGINE CRANKSHAFT FAILURE RESULTING IN A STALLED OR DISABLED VEHICLE.ODI'S INVESTIGATION DETERMINED THAT THE NATURE OF THE CRANKSHAFT FAILURE IS SUCH THAT THE ENGINE MAY CONTINUE TO RUN AND THEREFORE POWER ASSIST MAY NOT IMMEDIATELY BE LOST.THE AIR BRAKES WOULD CONTINUE TO FUNCTION REGARDLESS OF THE FAILURES SINCE, IN THIS APPLICATION, THE TRUCKS HAVE ADEQUATE AIR PRESSURE IN RESERVE TO MAKE A SAFE STOP.OUR ANALYSIS INDICATES THAT THE MAJORITY OF CRANKSHAFTS THAT ARE GOING TO FAIL HAVE ALREADY FAILED AND FUTURE FAILURES WOULD BE RANDOM AND NORMAL END OF LIFE CYCLE EVENTS.AFTER 7 YEARS OF SERVICE, THERE ARE NO KNOWN CRASHES, INJURIES OR FATALITIES AS A RESULT OF THE ALLEGED DEFECT.BASED ON ODI'S ANALYSIS, THIS INVESTIGATION IS CLOSED.FURTHER USE OF THE AGENY RESOURCES DOES NOT APPEAR TO BE WARRANTED.THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT NO SAFETY-RELATED DEFECT EXISTS.FULL TECHNICAL DETAILS ARE AVAILABLE IN ODI'S CLOSING REPORT.