Every year, many people are injured and some are killed in ‘wheel-off’ accidents. This is where the vehicle’s wheel comes off while the vehicle is moving. It’s a 70kg rolling missile which can cause serious damage if it runs into a person or vehicle.
Car wheel nuts tend not to come loose, but heavy vehicle wheel nuts are under much more stress and suffer more vibration which works them loose over time. Truck drivers should be conducting a pre-trip inspection every day to improve the chances of detecting this before it becomes a problem. Truck wheel nuts should be tightened by a trained person using the correct torque wrench.
How can you tell if your wheel nuts have come loose?
If there’s a wheel nut missing, or you can move it with your hand, it’s been loose for a long time. Wheel nuts work their way loose gradually and it causes wear on the wheel as it vibrates against the thread on the bolt.
Often, though, you can’t tell if a wheel nut is loose?
Many heavy vehicle drivers now use plastic indicators on their wheel nuts.
These sorts of plastic indicators can be useful to diagnose other issues, for example if there’s a sticking brake or a dry wheel hub, the heat caused will melt, warp or discolour the plastic.
Keeping a heavy vehicle’s wheel nuts tight is something for a professional to do as it’s easy to over-torque the bolt and damage it. It’s best if you have a system in place to check the wheel nuts periodically.