R. Scott King, BSME, CFEI, Principal Automotive/Mechanical Engineer

Car outer joint, driveshaft and control arm close-up. Inspecting a used front wheel drive vehicle by Ivan Radic is licensed under CC BY 4.0

Case Summary:  The right front passenger of a late-model SUV was severely injured when an object lying in the roadway was struck by a preceding vehicle, became airborne, and entered the vehicle through the windshield.  Police responding to the scene recognized the object and quickly alerted other units to a possible disabled truck in the area.  Within minutes, police discovered a disabled tractor trailer a short distance ahead of the initial incident scene.  Upon inspection, police discovered why the truck was disabled, and further identified the component that had struck and injured the passenger a few minutes earlier: a driveshaft. 

Expert Analysis:  A forensic examination revealed evidence of progressive wear of the driveshaft universal joints, located at both ends of the driveshaft.  Over time, this wear became so great that the joints failed, resulting in complete separation of the shaft from the vehicle.  Data collected from the driveshaft, including manufacturer information and component part numbers, allowed engineers to identify the components as well as their respective maintenance requirements.  A review of the truck’s maintenance records revealed that important chassis lubrication recommendations were not followed.  These recommendations specifically included lubrication of the driveshaft universal joints – the same components that failed on the incident driveshaft.

Result:  This information allowed engineers to conclude that lack of proper maintenance and vehicle inspection greatly contributed to this unlikely incident.  The matter was settled early in the litigation process.

R. Scott King, BSME, CFEI, Principal Automotive/Mechanical Engineer with DJS Associates, Inc., can be reached via email at experts@forensicDJS.com or via phone at 215-659-2010.

Categories: Automotive | Mechanical Engineering | Principal Automotive/Mechanical Engineer | R. Scott King, BSME, CFEI

Tags: Driveshaft | SUV | Tractor Trailer | Universal Joints | Vehicle Inspection