Calls for tougher towing laws

There are already a number of regulations around what type of vehicle can tow a caravan with a car licence, but the Caravan Council of Australia wants more rules to prohibit certain vehicles from towing heavy caravans, even when they are rated to do so.

The CCA's Colin Young argues that despite tow ratings of up to 3500kg, some tow vehicles including popular dual-cab utes are unsuitable for towing heavier caravans in a safe manner.

"There have been too many serious and tragic accidents, and many more frightening incidents, involving caravans on our roads," Young explains.

"Obviously driver, road, and atmospheric issues frequently partially contribute to the cause of these events, along with mechanical failures of the tow vehicle or caravan.

"However, in numerous instances, the prime cause has been the fact that the tow vehicle was not suitable for towing the particular caravan."

Young argues that only tow vehicles that weigh more than the trailer; have sufficient engine performance, and minimal tow bar 'overhang', should be legally allowed to tow heavier 'vans.

According to Young, the loaded weight of the tow vehicle should be at least 30 per cent more than the weight of the loaded trailer. In other words, to safely tow a caravan weighing 3500kg you need a loaded tow vehicle weighing no less than 4550kg.

"This figure is for a mature experienced driver with sharp faculties, especially reflexes, on good roads, in good weather, and with both vehicles in good mechanical condition. It is paramount that the tail never wags the dog," he says.

The tow vehicle should also have sufficient engine performance to enable it to keep up with traffic, accelerate up hills and safely overtake if required.

Young has previously argued that the ratio for engine power should be at least 25 for kW to GCM (tonne), and for torque, more than 65 for the ratio of Nm to GCM (tonne).

So in the case of a tow vehicle with a Gross Combined Mass (GCM) of six tonnes (for example, a typical dual-cab ute towing a three tonne-plus van), it should have at least 150kW and 390Nm.

He also argues that tow bar overhang, as measured from the centre of the rear axle to the centre of the towball, should be no more than 30 per cent of the tow vehicle’s wheelbase to ensure sufficient stability when towing.

"The distance from the coupling to the rear axle of the tow vehicle is critical. The shorter, the better," he says.

"Semi-trailers and 5th-wheelers have the coupling or king-pin virtually directly above the rear-axle, and (this) provides predictable handling on curves.

"Caravans have the coupling a long way behind the rear axle, and (this) provides undesirable and potentially lethal handling on curves. When the driver turns the steering wheel to move in one direction, the front of the caravan moves in the opposite direction," he says.

Young believes government regulatory bodies, including the Federal Department of Transport which oversees Vehicle Safety Standards, should as a high-priority action "produce a guideline, or preferably legislation, regarding the prime requirements for a tow vehicle, to best ensure safe towing of a caravan".

More detailed information on choosing a suitable tow vehicle can be found on the CCA website.