Wheel-off accidents involving commercial trucks are rare, but when they occur, the consequences can be catastrophic. In a recent article by tire safety expert Kevin Rohlwing, the importance of regular torque checks and proper wheel installation is underscored by a real-world incident that could have turned deadly.
Earlier this year, a set of dual tires from a semi-truck broke loose and struck a vehicle near the I-80 Truck Stop in Walcott, Iowa. The collision caused the car to flip multiple times, resulting in serious injuries to the driver. Thankfully, the vehicle was traveling in the same direction as the semi-truck. Had the tires approached from the opposite lane, the incident could have been fatal.
With over 13.5 million registered commercial motor vehicles in the U.S., including nearly 3 million tractor-trailers, that equates to more than 126 million truck tires on the road. Given the sheer volume, it’s remarkable that wheel-off incidents are relatively infrequent. However, when they do happen, they serve as stark reminders of the importance of safety protocols in wheel installation.
At the heart of Rohlwing’s message is the RIST Procedure—a standardized process technicians use to ensure proper clamping force during wheel installation. While torque wrenches have become more precise and sophisticated, they only serve as part of the solution. The real key to preventing wheel-offs lies in generating the correct clamping force, which secures the wheel to the axle.
Even when a technician follows every protocol, including using a calibrated torque wrench and applying torque in a star pattern, previously fatigued studs can lose tension during operation. These studs may appear fine initially but begin to fail under stress, causing wheel nuts to loosen without noticeable movement.
To mitigate this, Rohlwing and commercial tire dealers recommend a torque check after 50 to 100 miles of driving. This additional step can reveal loosening caused by stud fatigue or improper initial torque. Even if fleets find this interval inconvenient, driving over speed bumps or making sharp turns shortly after installation can simulate the flex and stress required to expose weaknesses.
Technicians, dealers, and carriers each share a portion of the responsibility in wheel safety. Technicians must follow the RIST Procedure accurately, dealers must uphold their torque programs, and carriers must enforce post-installation torque checks. Skipping any of these steps can lead to serious, avoidable accidents that endanger lives and threaten the integrity of a fleet.
Ultimately, while modern tools and training improve safety, there is no substitute for vigilance and follow-through in preventing wheel-off accidents. As the Iowa incident makes clear, a single loose wheel can change—or end—a life in an instant.
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