What is the first thing that comes to mind when you hear the term "4x4" or four wheel drive? A big powerful machine, capable of driving over large obstacles and through rough terrains? On the one hand, yes, that might be true. But these days, even some of the fanciest utility vehicles or sports utility vehicles are also classified as 4x4's.
So what exactly does the abbreviation 4x4 refer to? Quite simply put, the first figure is the total number of wheels on the vehicle and the second is the number of powered wheels.
Where a front wheel drive only gets power on the front two wheels (pulling the car forward) and a rear wheel drive only on the back two wheels (pushing the car forward), a 4x4 has the advantage of power on all four wheels. The four-wheeled vehicle has a drive-train that allows all four wheels to receive torque from the engine simultaneously. Experts say powering all four wheels provides better control than normal road cars on many surfaces.
So does that mean there is always power on all 4 wheels? Not necessarily…
Some four wheel drive vehicles allow the driver to manually switch between two-wheel drive mode (if available) for everyday driving and four-wheel drive mode for low traction conditions such as ice, mud, snow, slippery surfaces, or loose gravel.
Other models like the all-wheel drives (full time four-wheel drive) are usually known for their exceptional road handling capabilities, especially in turns or on slippery surfaces where it's really important to have proper grip!
Part time four wheel drive systems are mechanically simpler, cheaper, and tougher than all-wheel drive systems, and inherently better at making use of available traction. These systems are equipped with a gear reduction setting that multiplies torque for greater power at lower speeds, a vital feature for vehicles that will see much off road use. The drawback is that because it lacks a centre differential, a part time system can only be used in low traction situations where the wheels have the ability to slip as needed.
Some four wheel drive systems are extremely advanced. Say for instance you are on piece of muddy road and your front left wheel looses traction - the drive system then automatically removes all power from the front left wheel and distributes it to the other 3 wheels, ensuring that the wheel in trouble is quickly "pulled out of trouble". If you were in this same scenario with a front wheel drive car, you will only have one powered wheel left which would not necessarily be as effective.
It is very important to know the handling of your four wheel drive vehicle. If you are buying a 4x4 for the purpose of off-road driving, make sure that you go for proper training. Trained professionals have "been there and done that" and are really the best people to learn from. The last thing you want is your brand new 4x4 vehicle to end up in a ditch with all 4 wheels in the air - let's face it… Not even FOUR powered wheels would help you then!
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If you want to find out more about how Tata's 4x4 cars will help you with your off road adventures, visit www.tatasa,co.za