Ask an expert

My wife and I are taking a winter road trip through the South Island in July. While I've driven on gravel before, I've never used snow chains or hit black ice.

We will have a rental car, ie, unfamiliar vehicle. What should we watch out for on the road to avoid black ice, and when should we stop and fit chains?

Any other winter driving tips welcome.

Martin

From the "Ask Jack" archives - 22 January, 2010

Driving on snow or ice is completely different to driving on gravel. The biggest dangers are excessive speed, sudden changes in direction, take off and sudden stopping.

The best advice is to drive smoothly and expect the unexpected. Imagine an egg placed under your right foot when you use the throttle and brake pedals.

When you take delivery of the vehicle, ask the hire company about the use of snow chains. If possible get them to supply the chains and ask for a demonstration on how to fit. Chains must be compatible with the road wheel, there are no 'one chain fits all' options.

Make sure the chains are fitted to the driving wheels, for example a front wheel drive car means chains to the front. If you are hiring a 4WD and it can be locked in 4WD mode then chains to front also.

We always strongly recommend plenty of practice before you venture out on your journey.

Fitted chains should be firm but not tight and need checking for security after a short drive. Vehicle speed should not exceed 25kph if you are a novice in snow conditions.

Remember to carry some good quality warm gloves and coat as fitting chains in the cold is not pleasant and fit the chains well before you get stuck.

In some situations you are better to delay your travel if conditions are severe.

Black ice is very dangerous as drivers can lose sudden control of their vehicle. Once again be prepared, drive slow and avoid sudden braking or changes in direction. Black ice can sometimes be detected by a shiny watery black patch sitting on the road surface.

A few pointers worth noting:

- Be seen by others, drive with your lights on
- Drive expecting the unexpected
- Although you are an experienced driver, don't be overconfident
- Leave a big gap to the car ahead of you
- Avoid sudden movements
- Look further ahead than normal and anticipate change
- Black ice is common in shaded areas, around waterways and lakes
- If you encounter a skid or slide, take your foot off the accelerator and turn the steering wheel in the direction the vehicle is moving to help gain control
- Update yourself of the road conditions (AA Roadwatch, Transit NZ)
- Warm the engine before starting any travel, and use the airconditioning to dry the interior and keep the windsceen clear
- If conditions are severe, stay indoors and delay your travel plans