Trailer Structural Cracks

What NHTSA is examining

This investigation was open based on information ODI received through Early Warning Reporting.After gathering data, interviewing fleets and analyzing the available information ODI has not identified a safety defect trend.In response to an ODI request, Cornhusker reported 36 warranty claims related to the alleged defect.None of the claims resulted in a loss of vehicle control.In all cases the driver identified the component failure and placed the vehicle out of service without incident.ODI was concerned that a structural member failure would allow the trailer to separate or to drop down and contact the drive tires and increase the risk of a crash.However, no reports of these conditions were received. ODI also requested fleet contact information and spoke with five fleets.When asked if this condition created a safety risk, none answered affirmatively.All responding fleets were easily able to identify the failure and get it corrected without injury or property damage.Cornhusker provided a finite element analysis (FEA) of the failure area that showed how the structural members were failing and explained that the area in question was ahead of the kingpin and centered in the middle of the trailer.Cornhusker stated that even in cases of extreme neglect and failure, the pin plate bowed up slightly, but showed no signs of the trailer separating or falling down on the tractor driving wheels.In comparing the failure mode on the trailers subject of this investigation with trailers that…

Vehicles under investigation