Wheel detachment from commercial vehicles such as trucks, trailers, and buses has become a major problem in North America.  Wheels separating from such vehicles at speed cause a large number of very serious accidents each year, some with devastating consequences for all involved.

Despite increased spending on training and almost unprecedented preventive maintenance practices, fleets are still experiencing loose wheel nuts and wheel separations.  This is likely due to the complex and unpredictable nature of the problem.

Wheel nuts can loosen for a variety of reasons. The graphic below illustrates how a single loose nut can progress quickly during transit into multiple loose or missing nuts, and then into an assortment of increasingly costly events.