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Will your next vehicle be 2WD, AWD, or 4WD? Ask yourself: are you buying a minivan to transport a large family, a high-performance sports car, or a truck to take off-road? Do you live in an area with dirt roads or long winters? Is fuel economy important?
In two-wheel drive (2WD) vehicles power goes either to the front or rear wheels. Most of today’s cars are front-wheel because it allows more passenger room and may make control in slippery conditions easier. Trucks and sports cars built for towing or handling likely have rear-wheel drive.
Many models of both front and rear 2WD vehicles have traction control to help prevent wheel spin on slippery roads. When the drive wheels cannot grip the surface it is not much help.
What will help? Vehicles with four-wheel drive (4WD) or all-wheel drive (AWD) systems are heavier and all four wheels get power when engaged. While the weight impacts fuel economy, 4WD or AWD furnish better traction when drivers encounter certain weather and road conditions.
One advantage of a 4WD system is its low-range gearing. Not available in AWD vehicles, the ‘4 low’ enables off-roaders to drive through deep waterways and up steep hills.
How traction control works
You are stopped on wet pavement. You accelerate too quickly and your wheels begin to spin. With traction control the system reacts immediately and applies a braking force. Your car maintains stability and enhances safety.
AWD vehicles continually provide power to all wheels, a benefit when road conditions changed unexpectedly. Some new AWD systems can be called automatic AWD. They act as a 2WD system until the primary tires (either front or back) loose traction. Then, until traction is regained, all four tires automatically get power to help the vehicle regain stability.
The desire for better traction is one reason that AWD or 4WD vehicles account for almost 25% of today’s car and truck sales. Know the differences before you decide.
Article by: St. Louis Public Library staff