Towing of Trailers

Towing – All Variant Trailers are suitable for Australian roads.

# Please check if this differs from your state road rules. All towed trailers do not like speed, here at Variant we do not advocate traveling with a trailer over 100km. Towing at speeds over 100km greatly increases risk of accidents.

Towing a trailer requires additional knowledge and skill. All trailers, including caravans, affect the performance of the towing vehicle and its driver.

They affect fuel consumption, acceleration, braking ability, general control and maneuverability. These effects worsen as the size and weight of the trailer increase relative to that of the towing vehicle. The extra length and width can be hard to manage, with wind, road roughness and passing vehicles having a greater effect than on the vehicle alone. This puts additional responsibilities on a driver.

The information on this page applies to vehicles not exceeding 4.5 tonne gross vehicle mass (GVM)

Rules for towing

  • Towing more than one trailer at a time is not allowed
  • Nobody is allowed to ride in trailers or caravans
  • When towing and driving on a road without street lights, drive at least 60 metres behind heavy vehicles or other vehicles towing trailers,unless overtaking
  • Learner drivers and learner and provisional motorcycle riders are not allowed to tow
  • P1 car licence holders can tow small trailers with up to 250 kg of unloaded weight.

The driver

Driving with a trailer takes practice. Remember:

  • Allow for the trailer’s tendency to ‘cut-in’ on corners and curves
  • Allow longer distances for braking,overtaking and joining a traffic stream
  • When reversing, it is advisable to have someone outside the vehicle giving directions
  • Avoid sudden lane changes and changes of direction
  • Look further ahead than normal so you can react to changes in traffic or road conditions
  • Use the accelerator, brakes and steering smoothly and gently at all times
  • Use a lower gear when traveling downhill to increase vehicle control and reduce strain on brakes
  • Slow down well before entering corners and curves
  • Trailers tend to jerk the back of the vehicle around and can cause sway (snaking).If a trailer starts to sway, the vehicle’s brakes should not be applied, except as an absolute last resort.If the trailer’s brakes can be operated by themselves they should be applied gently, otherwise a steady speed or slight acceleration should be held if possible until the sway stops
  • Take care not to hold up traffic unnecessarily
  • Plan more rest stops and shorter traveling days as towing is more stressful and tiring than normal driving
  • There is no specific speed restriction while towing a trailer. However, the posted speed limits must not be exceeded.Always drive to the road,traffic and weather conditions.

Before each trip, check:

  • Vehicle and trailer are roadworthy.
  • All tyres are properly inflated.
  • Trailer’s wheel-bearings, suspension and brakes work properly.
  • All lights work and safety chains are properly connected.
  • Oil,water,brake fluid,battery and other service checks on the vehicle.

At regular intervals during the trip, check:

  • Couplings, all doors, hatches, covers and any load or equipment are still properly secured.
  • Tyres are still properly inflated and not rubbing on suspension or body work.

If travelling to another State, check with the relevant roads authority whether there are different rules.

The towing vehicle

Vehicles must be suited to the trailer. Vehicle manufacturers usually indicate in the owner’s manuals the maximum weight and other features of trailers appropriate for the vehicle.These limits should not be exceeded.

Registration:

  • All vehicles must comply with all relevant standards for registration and be roadworthy at all times
  • Rear number plates and lights must not be obscured by the towbar when there is no trailer connected.

Towing vehicles must be properly equipped with:

  • Towbars and couplings of a suitable type and capacity
  • Electrical sockets for lighting
  • Brake connections if the trailer is fitted with power or electric brakes.

Additionally:

  • Extra mirrors may be needed for the towing vehicle if towing a large trailer
  • For vehicles with automatic transmission, an extra transmission oil cooler may be needed
  • Some vehicles need structural reinforcement and/or special suspension and transmission options and load-distributing devices to be able to tow heavier trailers.

1 The 3,500kg Towing Capacity is Exact

There are a lot of vehicle advertisements that include information on a 3,500kg (3.5 tonne) towing capacity for new vehicles. However, the number that drivers should really be focused on is the Gross Combined Mass (GCM). The GCM determines the actual legal weight maximum or your vehicle and your trailer together. Some drivers are astonished that they cannot tow a 3,500kg load as advertised. They would actually have to reduce that towing amount by the weight of their own vehicle to stay within the legal GCM limit. If you’re in any doubt about the real towing capacity of your vehicle consult your owners manual for more detailed information. e.g. -the GCM on a Hyundai Iload is

2 Accelerating Can Correct a Swaying Trailer

There is no electronic trailer control system that corrects trailer sway by using acceleration. In fact the faster you’re travelling the more unstable everything becomes. When a towed load begins to sway you will need to ease off the accelerator to reduce your speed and avoid a sudden transfer of weight. Then you can gently apply some pressure to the brakes to bring your trailer under control. This procedure can be quite stressful and you may need some time to calm down afterwards. Once the situation has returned to normal try to find out what caused the trailer sway and correct the problem.

3. Towing Can be Carried Out Safely at the Speed Limit

As we demonstrated above a towing vehicle and trailer is inherently unstable when travelling at speed. This is because there is a lot of inertia in play and the trailer will always want to take the path of least resistance by travelling straight. If you need to turn or swerve the trailer will not want to follow your vehicle and you may lose control. Many novice towing drivers believe that the posted speed limit applies to towing vehicles as well. This is a dangerous misconception and you need to check your owners manual for the manufacturer’s recommended peak towing speed limits. If you’re in any doubt travel under below the posted speed limit, if the speed is lower you will have more time to react and an accident will be less severe.

Tow bar

A properly designed and fitted towbar is essential for towing. The rated capacity of the towbar and coupling should not be exceeded.

The towbar should be clearly and permanently marked with its:

  • Maximum rated capacity
  • Make and model of the vehicle it is intended for or the manufacturer’s part number
  • Manufacturer’s name or trade mark.

This is compulsory for vehicles built after 1 January 1992. The exception is where the towbar is a permanent part of the vehicle.

Towbars must not protrude dangerously when there is no trailer connected.

Load equalisers

Load equalisers can be used when towing large caravans. Load equalisers:

  • Help the vehicle retain normal suspension height and effective steering control
  • Transfer some of the weight from the towbar to the front and rear suspension of the vehicle.

As load equalisers may overload the towbar and its components, check with the towbar manufacturer for advice before use.

The trailer

Trailers must be a suitable size and type for their intended tasks. They must be built to meet the standards for registration. If a trailer is required to be registered it must be fitted with a rear number plate.

Towing ratio requirement

The loaded mass of the trailer must not exceed the lesser of:

  • Rated capacity of the towbar and tow coupling.
  • Maximum towing capacity of the vehicle.
  • Maximum carrying capacity of the trailer.
  • Maximum rated carrying capacity of the tyres.

If the vehicle manufacturer has not specified the maximum towing mass, the maximum towing mass is:

  • One and a half times the unladen mass of the towing vehicle, provided that the trailer is fitted with brakes which are connected and in working order, or
  • The unladen mass of the towing vehicle if the trailer does not require brakes.

Vehicles with a manufacturer’s gross combination mass (GCM) more than 4.5 tonne may tow in accordance with the above requirements.The GCM is the gross combination mass of the car and loaded trailer.

Braking system

The minimum braking system for a trailer depends on the type of trailer, its weight and the weight of the vehicle:

  • 0 – 750 kg loaded weight – no brakes required.
  • 751 – 2000 kg loaded weight – braking on both wheels on at least one axle.
  • 2001– 4500 kg loaded weight – braking on all wheels, and an automatic breakaway system in case the trailer becomes detached from the vehicle.

Towing coupling

All couplings:

  • Must be strong enough to take the weight of a fully loaded trailer.
  • Should be marked with the manufacturer’s name or trade mark and rated capacity.
  • Must be equipped with a positive locking mechanism. The locking mechanism must be able to be released regardless of the angle of the trailer to the towing vehicle.

Safety chains

  • Must comply with Australian Standards.
  • Trailers less than 2500 kg when loaded must be fitted with at least one safety chain.
  • Trailers over 2500 kg when loaded must be fitted with two safety chains.

To prevent the front end of the drawbar from hitting the ground if the coupling is disconnected,safety chains must be:

  • As short as practicable and connected to the towing vehicle.
  • Crossed over if two chains are fitted.

Loading trailers

It is important that trailers are not overloaded and that loads are properly secured to or contained within the trailer:

  • A load must not project more than 150mm beyond the trailer’s width or be more than 2.5m overall width, whichever is less
  • Loads that project more than 1.2m behind a trailer must have a red flag attached to the end of the load. This flag must be at least 300 mm square and clearly visible. To avoid having an overhanging load, you should purchase a trailer that suitably contains the load
  • Between sunset and sunrise, or when there is insufficient daylight, a clear red light or at least two red reflectors must be fixed to the end of any projecting load
  • Overall length of the vehicle and trailer combination including its load must not be more than 19m
  • To reduce sway, heavy loads should be concentrated towards the centre of the trailer
  • Loads should be kept as low and as close as possible to the axle or axles with about 60 per cent of the total weight forward of the centre of the axle or axles. As a general rule, about 5-10 per cent of the total mass of the trailer plus load should be supported by the vehicle through the coupling. The trailer drawbar should be level or slightly ‘nose down’
  • Loads must be covered to secure and contain all materials within the vehicle and trailer. Fines apply for uncovered loads.
 For more information contact -http://www.rms.nsw.gov.au/roads/safety-rules/road-rules/towing.html

The information given in this section is a guide only and is subject to change at any time without notice.

This information is also available in the Road Users Handbook.

You can access the full text of the NSW Road Rules on the NSW Legislation website.

True maximum legal loading

For example, say your vehicle has a Kerb Mass of 2500 kg, a GVM of 3500 kg and a GCM of 5000 kg.

At its Kerb Mass of 2500 kg the manufacturer says it can legally tow another 2500 kg, but that towing weight decreases in direct proportion to how much the tow vehicle’s weight (tools, spare parts etc) increases. So if you loaded up the towing vehicle to its GVM of 3500 kg (or a payload of 1000 kg), that would only leave a towing capacity (trailer & its contents) of 1500 kg to meet the GCM of 5000 kg. If the towing vehicle’s GVM dropped to 3000 kg (or a payload of 500 kg), it’s towing capacity (trailer & its contents) would increase to 2000 kg and so on.

These are some scary towing figures claimed by some manufacturers and they should all carry a large asterisk and warning of this fact!

Tow Bar Download (TBD)

The amount of weight on your tow bar is crucial to safe and efficient towing and needs to be mentioned here. Any quality tow bar will have a placard or similar showing the maximum tow bar capacity (kg) and maximum tow bar download (kg). Make sure the tow bar you choose is designed specifically to suit your vehicle and your towing capacity requirements.

Typically the TBD should also be around 10-15 percent of the Gross Trailer Mass (GTM), which for peace of mind can also be calculated using the GTM and TBD figures as shown here: TBD divided by GTM x 100 = % of GTM