The importance of trailer-coupling maintenance

Like any other heavy vehicle component, tow couplings are subject to wear and tear. Consequently, regular inspection and maintenance are essential to ensure they remain in good condition.

The National Heavy Vehicle Regulator (NHVR) provides guidelines on inspecting and maintaining tow couplings. These guidelines are designed to ensure that heavy vehicle operators comply with safety standards and that their vehicles are in good working condition.

Getting into the habit of conducting regular inspections of tow couplings is not only good business but essential in identifying any signs of wear and tear. It enables operators to detect any potential problems early and take corrective action before they become more severe.

During inspections, operators should check the coupling for any signs of cracks, deformities, and wear on the coupling pins. They should also ensure that the coupling components are correctly aligned and securely fastened. However, more frequent inspections may be required on vehicles operating in severe conditions, such as those working in dusty conditions or travelling on extremely rough terrain.

It is essential that operators follow the manufacturer's instructions when carrying out maintenance on tow couplings. They should also keep records of all maintenance activities and inspections carried out on the coupling. This is important in demonstrating compliance with safety standards in case of an accident or inspection by the authorities.

Frequent examination and maintenance of tow couplings offer several benefits to heavy vehicle operators. First, it enhances safety on the road. A well-maintained and regularly inspected coupling reduces the risk of accidents caused by the trailer unintentionally detaching from the truck. Such accidents can lead to severe injuries, loss of life, and property damage. Regular inspection and maintenance also ensure that the coupling can withstand the stresses of heavy loads and long journeys without breaking down, which further enhances safety.

Second, regular inspection and maintenance of tow couplings can save operators money in the long run. A well-maintained coupling lasts longer and requires fewer repairs and replacements, reducing downtime and repair costs. Routine inspection can also detect potential problems early, allowing operators to take corrective action before they become more severe and costly to repair.

Finally, regular inspection and maintenance of tow couplings demonstrates compliance with safety standards set by the NHVR. It shows that operators are committed to ensuring the safety of their drivers, other road users, and the cargo they transport. It also reduces the risk of penalties and fines for non-compliance.

The importance of compliance hit home recently when the Court of Appeal heard the $210,000 fine and conviction initially imposed on a Wodonga-based mechanical business last year was manifestly inadequate.

The following extract from a recent Worksafe information notification highlights the importance of regular inspection and maintenance of tow couplings.

In June 2021, the Wodonga County Court found Heavy Mechanics guilty of a single charge of failing to ensure, as far as reasonably practicable, that people other than employees were not exposed to risks to their health and safety. The court heard that in August 2014, a petrol tanker serviced by the company de-coupled on the Wodonga-Yackandandah Road at Staghorn Flat.

The detached trailer crossed the road and struck two cars travelling in the opposite direction, killing all three occupants, including a four-year-old child.

A subsequent WorkSafe investigation found that the tow-eye coupling connecting the prime mover and trailer was excessively worn and failed under load. At the time of the incident, it had been used for over three years and travelled 350,000 kilometres.

The court heard Heavy Mechanics had serviced the truck just days prior to the incident, including testing the tow-eye coupling, but that testing did not involve an accurate visual inspection or testing while the truck was detached from the trailer, and that this had limited the ability to inspect the parts involved.

Manufacturers provide detailed inspection and maintenance procedures freely online to make this task easier. They also have tools and gauges available to make performing checks easier.

All manufacturers recommend using straight rubber air lines on dog trailers and converter dolly applications. If the coupling fails and the trailer separates from the truck, the straight rubber hoses will only stretch a short length before breaking. As soon as the hoses break, the trailer brakes will apply, and the run-away trailer will come to a stop.

For this reason alone, the use of 'coiled' Suzi-coil airlines should be avoided at all costs in these applications.

Consequently, the importance of regular inspection and maintenance of tow couplings on heavy vehicle truck and dog trailers are essential in ensuring the safety of the driver, other road users, and the freight. The NHVR provides guidelines with clear instructions to aid operators in conducting inspections and maintenance.

You can access the NHVR Coupling Maintenance information by clicking here.