The Causes of Wheel-Off Trucking Accidents

As the name implies, a wheel-off trucking accident occurs when a large truck loses one or more wheels while on the road. When a wheel separates from a semi-truck, it can strike a pedestrian, crash through the window or glass door of a building, or strike other motor vehicle traffic. Some of the worst accidents occur when a wheel crosses into the lane of oncoming traffic and collides head-on with a vehicle.

Wheel-off accidents are usually caused by improper tightening of the wheel lug nuts. Here are three common ways this happens:

The Lug Nuts Are Over Tightened

Lug nuts hold a tire in place because their thread pulls against the wheel stud threads. When severely over tightened, the stud is over stressed close to the failure point of the stud metal. Traveling on the road then adds additional stress that causes the stud to break. Several broken wheel studs can cause the wheel to come off.

Over-tightened lug nuts can happen when air powered impact wrenches or nut runners use too much air pressure, or when using a lubricant on stud-piloted wheels, which don't require lubrication. Using an ordinary wrench instead of a torque wrench may cause this problem as well.

The Lug Nuts Are Under Tightened

Insufficiently tightened lug nuts can work loose from road travel vibration and cause a wheel-off accident. This can happen when pneumatic nut tightening tools are set to the wrong pressure or when torque wrenches aren't used.

Rust, dirt, and other contaminants in the threads of the nut or stud prevents the nut from seating with the proper force even when tightened with the correct torque. A similar effect happens when lubrication isn't applied to hub-piloted wheels.

The Lug Nuts Aren't Tightened in the Proper Sequence

Lug nuts should be tightened in pairs across the wheel's diameter. This ensures that the wheel is held against the hub with a uniform clamping force.

In addition to posing a danger to others, a wheel-off can cause the truck driver to lose control of his own rig. This is especially true if a front wheel of the tractor comes off. If a trucking accident injured you, get legal advice from our experienced lawyers. For more information, or to schedule a free consultation, contact us.