Author: Tony Allardyce

DEFINE WHAT YOU WANT
o More seats or a bigger tray?
o Fuel. Petrol is increasingly popular with the rising cost of Road User Charges. But if you do high km’s and/or tow heavier loads, diesel is better
o Tonneau cover, hard lid or canopy all have their pros and cons in terms of load size, weather and security. It will be cheaper to buy the vehicle complete than to buy extra’s separately. Thinking through what you’re using it for before you buy could save you a lot of money afterwards
o Tow rating. Remember, there’s no insurance if you go over. And is a braked tow rating of, say, 3500kg really going to cut the mustard for extended periods of towing behind a vehicle which weighs a lot less? Safety, comfort and compliance are important considerations
o Manual or auto? Manual is often preferred for carrying/towing heavy loads and off-road use
o Brand tax. Certain brands command a premium. Are they really that much better? Google ‘common problems with…’ and you might be surprised. Every vehicle has its issues. A lesser known vehicle here may already be a big auto manufacturer elsewhere. You may decide the lower capital cost of one of them more than offsets the lower resale value at the other end

There are two sizes of tow ball commonly used in New Zealand – the NZ standard 1″7/8ths (47.5 mm) and the 50mm. The 50mm is commonly found on European and American vehicles.

The larger tow ball will not fit a smaller coupling. But, take care not to use the smaller tow ball in a larger coupling; they can come apart. We see it often when people are towing imported caravans and floats.

The tow ball size is stamped on top of the tow ball itself.

Incidentally, the tow rating of the whole tow bar will be on a plate on the tongue of the bar. If not, talk to a tow bar manufacturer who will be able to point you in the right direction. Without the tow rating on the tow bar, you may also fail a WOF. To determine towing capacity of the tow vehicle, you need to take note of the manufacturers specs for towing as well as the rating of the tow bar.

Maintain a regular maintenance routine. Keep to manufacturers guidance for oil change frequency and grade. Harsh driving and/or environment conditions may require more frequent oil changes. Replace the oil filter with a high grade filter each service. Turbo’s are also particularly affected by oil level. Avoid going beyond high and low oil levels on the dipstick. Check the oil feed and drain lines to and from the turbo. Pressure testing is recommended as visual inspections will not reveal what’s going on inside the lines. Air filters, which also affect turbo performance, may need changing more often in certain conditions (dusty for example). And, remember to warm your engine up and cool it down. Turning the engine off hot will cause deposits to build up and shorten the life of your turbo.

How much can your vehicle tow safely?

This guide is for cars, vans, station wagons, utes, 4-wheel drives and light trailers (vehicles whose maximum laden weight is less than 3.5 tonnes) or load weights less than 500kg.

For trucks, heavy trailers or loads of more than 500kg, refer to:
The official New Zealand truck loading code [PDF, 4.1 MB]

Most vehicles have tow ratings given to them by the manufacturer specifying the gross trailer weight braked, unbraked, or both, that the vehicle can safely tow. Although the law does not require these tow ratings to be followed, the NZ Transport Agency recommends that they be taken into account.

In addition to the requirements above, the law requires that every light vehicle and trailer combination must be capable of stopping within a distance of seven metres from a speed of 30km/h. In effect, this means that the maximum allowable weight of an unbraked trailer is limited by the weight and braking ability of the vehicle being used to tow it.

The Transport Agency recommends, as a guide, that the laden weight of an unbraked trailer should not exceed three quarters of the unladen weight of the towing vehicle and then only if the towing vehicle’s brakes and tyres are in excellent condition. A trailer heavier than this may prevent the vehicle combination from meeting the seven metre from 30km/h brake performance requirement. To illustrate the increase in stopping distance when towing an unbraked trailer, consider a trailer with a laden weight equal to the weight of the towing vehicle.

This combination can be expected to have double the stopping distance of the towing vehicle alone, and even a towing vehicle with good brakes is likely to fail the legal brake performance requirement of seven metres from 30km/h. If the trailer is equipped with brakes, it may be possible to safely tow a trailer heavier than three quarters of the unladen weight of the towing vehicle, but the seven metres from 30km/h brake performance requirement still applies.

Remember, too, to check the tow rating of the tow bar itself. It may differ from the tow rating of the vehicle itself.

With Road User Charges having gone up, we’ve noticed customers who would never have considered petrol doing so now. But, as with anything, there are things to think about first. A vehicle will go further on a tank of diesel. So, the more km’s you travel, the more viable diesel becomes. If you’re travelling much over 20,000km’s per year, consider diesel. Second, diesel is better for towing, especially up hill. Last for here, diesel engines are more rugged and tend to last longer if they’re well looked after. So, even taking into account a diesel vehicle costs more to buy and servicing costs are a bit higher, diesel beats petrol hands down under certain circumstances.