People wrongly believe that with 4WD, all the 4 wheels of the car runs and turns with the same speed simultaneously. When a 4 wheeler takes a turn, the inside tires spin with a lesser speed than the outside tires. Mostly vehicles come in two wheel drive that is 2WD. In 2WD, the engine power comes in either the front two wheels or the rear two wheels. Many vehicles such as the cars, wagons and the minivans come with 2WD because they are space efficient. The engine place is very small in such vehicles and there is more space in the inside for the passengers. In slippery conditions, there is more weight on the front drive wheels and wheels pull the car rather than pushing along the road. So the front wheel drive helps in such conditions. This also prevents the rear wheels from sliding sideways in slippery circumstances.
When it is a 2WD with the rear wheel drive, there is less or no demand on the front wheels. So they can be used totally only for the steering. Such are used mostly in pickups and SUV’s that do the heavy duties that includes towing. But rear wheel drive is common in sports car and high performance sedans because of its contribution to better handling. Traction control is available in many 2WD vehicles these days. This traction controls helps to prevent wheel spin by enabling to maximize traction at the drive wheels. It helps when the surface is very much icy, snowy or wet. But if there is no grip for either of the drive wheels, then traction control will be helpless. However when the condition is wintry, 4WD is better than traction control alone for getting up a slippery slope.
In case of AWD, power comes in all the four wheels. It is mainly helpful when the weather is rapidly changing and driving on a road with intermittent ice and snow. It is light and compact and this makes it compatible for wagons, car based SUVs, minivans and pickups. AWD gives maximum of the forward traction and proves help in conditions when driving over medium off terrain road.
However, there are limitations for the AWD and 2WD which are not very well accepted. In case of AWD, power goes to all the 4 wheels but only if you go on a straight line. It has nothing to do to improve your brake system and when cornering. So, this type will not enable you to drive with the same techniques and same speed as you would drive on a dry road.
In case of 4WD, comes a lower range gearing, which when selected, helps in off-road challenging conditions, for eg: tackling steep off-pavement hills, climbing over borders and fording deeper waters. This facility does not come along with AWD. Many times, AWD and 4WD are designated interchangeably in advertisements except that the 4WD gives you the above mentioned lower range gearing. And majority of the 4WD vehicle owners never requires this capacity. Also, 4WD vehicles are very costly, heavy and complicated which also compromises fuel economy.
Modern 4 wheel drive vehicles come as either automatic or full time. Automatic refers to vehicle automatically switching between the 2WD and 4WD mode, depending upon the condition of the road. Full time means they can remain engaged all the time. Some SUVs possess only part time 4WD. These require the driver to manually switch between the 2 and 4 wheel drive that requires the vehicles ability to offer maximum traction when the surface of the road abruptly becomes slippery.
When the weather condition is slightly rainy and snowy, 2WD should work best. Front wheel drive along with the traction control is recommended. When you encounter more severe problems like the high rocks, deep sand or the steep inclines, 4WD will work best. Both 2WD and 4WD are best in particular weather conditions.
How Much Traction Do You Need: 2WD or 4WD?
Last updated: