Off Road Driving Guide

INTRODUCTION

Four-wheel drive vehicles can master seemingly impossible terrain with consummate ease. Conversely, they can get hopelessly stuck in a flat field of grass. Whilst the vehicle and the choice of tyre are absolutely critical to successful off roading, it is ultimately the skill and competence of the driver that decides between an enjoyable drive and embarrassing failure. Here we explain the essential basics to put you on the right track to tackle routine off-road situations with confidence and in safety.

KNOW YOUR VEHICLE

The starting point is to thoroughly familiarise yourself with the vehicle by consulting the owners manual. Some vehicles are permanently in four-wheel drive mode, others have the option of selecting two or four-wheel drive according to the terrain. For fuel economy reasons alone it is preferable to select two-wheel drive for everyday road driving if possible, unless weather conditions dictate otherwise. Check if the vehicle has free wheeling hubs, and thoroughly understand the procedure for engaging, if applicable and selecting low ratio transmission.

DRIVING STEEP HILLS

Steep inclines are the most common off-road hazard and are potentially the most dangerous. Always travel in a straight line up or down a steep hill and check in advance to ensure that there is a clear exit at the top. When tackling an uphill section, select second gear, low ratio, and use a short run up to gain a little momentum. Try to gauge it so that you crest the hill at walking pace, no faster. This is the speed you should adopt for general off-roading in the interests of the vehicle, comfort and safety. Never try to change gear or direction once committed to a hill, and be prepared for the loss of vision as the sky fills the windscreen on a steep climb – it’s the reason you checked the hill beforehand. If you lose forward momentum, hold the vehicle on the brakes, quickly select reverse gear and let the engine braking control the descent while you look over your left shoulder holding the wheel with one hand to avoid oversteering. Do not use the accelerator.

Driving a steep downhill section needs first gear, low ratio. Once again, check the terrain in advance; making sure the hill isn’t so steep that the front of the vehicle will bury itself in the ground at the bottom. Take your feet off the pedals and let the engine braking take you down the hill at a constant speed, keeping in a straight line. Try to avoid travelling along a side slope. If you have to, keep as low down the slope as possible and be prepared to carefully turn downhill at the first hint of a problem, if in doubt don’t do it.

TACKLING DITCHES AND MOUNDS

Approach ditches or mounds at an angle to allow each wheel to tackle the obstacle individually, making the best use of the available ground clearance. Note that if the obstacle is too severe, it can cause the vehicle to become cross-axled, with the diagonally opposite wheels coming clear off the ground, resulting in no drive, the necessity of a tow or a long walk home. This is one occasion where the axle differential locks come into their own; as they put power to the two wheels that still have traction.

TRAVERSING MUD AND RUTS

Ruts deeper than the clearance under the vehicles axles will quickly have you stuck, so try to straddle them. If the ruts are shallow it is as easy to follow them. Avoid the temptation to fight the steering wheel and always keep your thumbs clear to avoid injury if the wheel spins suddenly. Deep mud is one of the few conditions when a little speed is called for. Build up speed gently before entering the mud and be prepared for sudden deceleration on contact. Stay in gear and take as straight a line as possible to firmer ground. Always attempt to gauge the depth of the mud and be prepared for the worst. If in doubt, reverse before it’s too late. If on exiting the mud, the tyres are clogged drive gently to clean the tread and restore traction.

CROSSING WATER

4x4 vehicles can frequently tackle water several feet deep, but always try to judge the firmness of the underlying surface before crossing. Water should never be driven through fast. A steady speed that creates a gentle bow wave is the correct method, in order to minimise drag and avoid flooding the engine. Always remember to drive a short distance with the footbrake lightly pressed on leaving the water in order to restore braking efficiency.

TYRE PRESSURES - OFF ROAD

In most conditions the vehicle can be driven off-road at the same recommended tyre pressures as on tarmac. However in really muddy, low-traction conditions it can be beneficial to lower pressures slightly to achieve better grip. It is vital that extreme caution is used in these circumstances, as it is possible the tyre can demount the rim if pressures are too low. Always re-inflate the tyres to the correct pressure immediately on returning to tarmac. Serious injury may result from under inflation.