Ask Phoebe: Sedan likely pushing it by carting horse around

Most vehicles have tow ratings given to them by the manufacturer specifying the gross trailer weight braked, unbraked, that the vehicle can safely tow. Photo / Thinkstock

Recently, on the motorway, I saw a Nissan Sunny sedan towing a hired horse float with horse aboard. It occurred to me that the car was too light for such a load. What are the rules surrounding towing weight limits? David Williams, Balmoral.

First, a few numbers. A Nissan Pulsar Sunny has a kerb weight of about 1000kg. A tandem-axle horse trailer capable of carrying one horse has a tare weight of 800kg or thereabouts. An adult horse of average breed can weigh between 350kg and 500kg.

A horse float with one horse aboard therefore weighs about 1200kg, which is clearly more than the unladen weight of the car.

The NZ Transport Agency recommends, as a guide, that the laden weight of an unbraked trailer (that's a trailer with braking ability controlled by the driver of the towing vehicle, either directly or indirectly) 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.

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. In addition, the law requires that every light vehicle and trailer combination must be capable of stopping within a distance of 7m 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.

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 7m from 30km/h brake performance requirement still applies.

Long story short; the Nissan Sunny may have been capable of towing the horse float, but I would not do it, and would not recommend it. I spoke to a local hire company, and the representative said they would advise against a small sedan towing a loaded horse trailer.

Recently I was reading the road code on extra vehicle lights. My interpretation was that those people who drive with these extra fog lights, dazzling oncoming drivers, are breaking the law? Is this correct?
At this time of year with wet roads, the people using these lights in addition to fitted head lights reflecting off the wet road surface make it difficult to see the road ahead for oncoming traffic. There seems to be little regard for the poor souls trying to see where they are going, specifically out of town on unlit roads.
Can you shed light (no pun intended) on the legal use of these extra lights please? If it is incorrect to use them will the police do anything to reduce accidents on the rural roads?
Ian Lawrence, South Auckland.

The NZ Police website advises that fog lamps should only be used when visibility is severely reduced, for example by snow or fog. It is against the law to use fog lamps in clear conditions (day or night) as they can dazzle other road users. You may be stopped by police for illegal use of additional lights on your vehicle, and you will be fined.