Driving Test Success PRACTICAL HOME --- MAIN PAGEDriving a 4X4 In a two wheel car, power is sent to either the front or rear wheels only. In a four-wheel drive vehicle, power is sent to the front and rear wheels. Depending on the system used, the vehicle may have permanent four wheel drive, or may switch between two and four-wheel drive, either manually or automatic, depending on the road conditions.

Not so long ago, four-wheel drive vehicles were rarely seen on the road; they were only really used by people who had a genuine need to drive off-road. Today, however, they are becoming ever more popular, and morphing into ever changing forms - estate cars, saloons and sports cars can now all be powered by four-wheel drive.

Four-wheel drive vehicles were originally built to work in all weather conditions and drive over difficult terrains, hence their bulky, sturdy design and elevated driving position.

Driving a four-wheel vehicle on normal roads requires no extra skill or knowledge. If the vehicle is an off-road type, you should be aware that, due to the higher centre of gravity, they can roll when going round corners at speed, this can make them less stable than a standard car. Some are also known to have very large blind spots which can easily obscure other road users.

Driving Off-Road Many four-wheel drive vehicles, even though they look capable of driving off-road, may have very limited off-road ability, but given the fact that they are unlikely ever to feel the touch of well-cut grass, this doesn't really matter. If you were to drive off-road in a suitable vehicle, always keep to safe driving principles.

Take into account the nature of the terrain - be cautious when driving on hilly terrain and soft surfaces. Don't push your vehicle to the limit. When cornering drive at a steady speed. Driving too fast can affect the stability of the vehicle. Look out for rocks. They can damage the underside of the vehicle or can deflect the steering, causing loss of control. Be realistic. Your vehicle isn't invincible. Even quality four-by-fours get stuck

Four Wheel Drive Saloon Cars Four-wheel drive is increasingly being fitted to saloon and other standard road cars. The main benefit of this is improved traction under all weather or road conditions.

However, such cars have their limitations; they aren't very good off-road, for example. Their low ground clearance means they cannot deal with very soft surfaces, such as mud, and although good in shallow snow, in deep snow they are likely to struggle.

Four-wheel drive also uses more fuel then two wheel drive.