Factsheet 13d — February 2005

Loading and towing a light simple trailer

Back to Factsheet 13d

Loading your trailer safely

If you tow a simple trailer, you need to be aware that the trailer can impose a large weight on the rear of your vehicle. This weight can, by lever action through the chassis of the vehicle, reduce the effective mass bearing on the front axle(s) of your vehicle. It is important, therefore, that you load your trailer carefully so the load is distributed centrally over the axle(s) of the trailer. This will allow your vehicle to maintain front-wheel grip on the road, so you can continue to steer it safely.

Note: There needs to be a small downward force on the tow coupling of a simple trailer, to ensure it remains stable while being towed.

The number of trailers you can tow

A light rigid vehicle may only tow one trailer.

Light tractors may tow two light trailers if the manufacturer's rating on the tractor allows this, and if the tractor doesn't exceed 50 km/h.

A heavy rigid vehicle (but not a bus) may tow two trailers under certain conditions.

See Factsheet 13c for more information on towing two trailers.

Requirements for passenger service vehicles towing a trailer

A heavy passenger service vehicle (eg, a bus) may only tow one light trailer with a gross vehicle mass up to 3.5 tonnes.

A light passenger service vehicle (eg, a van or taxi) may only tow one light trailer with a gross vehicle mass under 2.0 tonnes.

An articulated bus may not tow a trailer.

Speed of vehicles towing simple trailers

• Light vehicles towing a trailer are limited to a maximum open road speed of 90 km/h.
• Heavy vehicles towing a trailer are limited to a maximum open road speed of 90 km/h.
• School buses are limited to maximum open road speed of 80 km/h.

Drivers also need to obey any lower speed limits that apply on particular roads.

What to do about projecting loads

Vehicles may carry loads that are higher, longer or wider than the vehicle itself, provided the load doesn't exceed the maximum permitted dimensions for that class and type of vehicle, and provided the vehicle can be moved safely when loaded. It's the operator's responsibility to ensure the load is properly secured to the vehicle so the vehicle remains stable at all times.

You need to read Factsheet 53 (Overdimension vehicles and loads) if the load exceeds any of the standard dimension limits.

Loads that overhang the outside of the body or deck of the vehicle by more than one metre to the front or rear, or more than 200 millimetres to the left or right side, need to carry special warning devices attached to the overhanging end(s) of the load.

During the hours of daylight, there must be either:

• a clean white, or fluorescent red, orange or yellow flag, at least 400 mm long by 300 mm wide, or
• a frangible hazard warning panel, at least 400 mm long by 300 mm wide, showing an orange diagonal stripe (200 mm wide) against a yellow green background, facing forwards or rearwards.

During the hours of darkness, the flags or hazard panels must be replaced with lights attached to the load.

• Loads more than one metre wide and extending more than one metre from the rear of the vehicle must have one red lamp (facing toward the rear) on each side of load.
• Loads up to one metre wide and extending more than one metre from the rear of the vehicle must have one red lamp (facing toward the rear) at the centre of load.
• Loads more than one metre wide and extending from the front of the vehicle must have one white or amber lamp (facing toward the front) on each side of load.
• Loads up to one metre wide and extending more than one metre from the front of the vehicle must have one white or amber lamp (facing toward the front) at the centre of load.
• Loads extending more than 200 mm beyond the side of the body of the vehicle must have one red lamp (facing toward the rear) on each side of the load at the rear and one white or amber lamp (facing toward the front) on each side of the load at the front.

These lights need to be clearly visible in clear weather at a distance of at least 200 metres during the hours of darkness.

Displaying these lights at night is an operating requirement that applies to all vehicles, no matter when they were first registered.  

In the diagram above, the boat is the load on the trailer. It has a raised outboard motor that projects more than one metre behind the rear of the trailer.

If the distance from the rear of the trailer to the most rearward point of the load is more than one metre (and the projecting part is less than one metre wide), one warning device must be attached to the centre of the projecting part of the load:

• In daylight, this may be a flag or hazard panel (facing backwards).
• During the legal hours of darkness, this may be a red light visible from at least 200 metres away.

Where to get more information on towing, loading and braking requirements

Refer to the Land Transport New Zealand publications Towing and loading safely and Glovebox guide to safe towing and loading.