All-Wheel Drive Explained
While previously limited to just large trucks and SUVs, all-wheel drive and four-wheel drive are now available for virtually all vehicle types, including sedans, compact SUVs, and even sports cars.
An increasing number of vehicles now come standard with all-wheel drive as well. According to a study by research agency iSeeCars, over 50 percent of all new vehicles sold in half of the United States are equipped with either all-wheel drive or four-wheel drive, with northern states like Montana and Wyoming with over 70 percent adoption.
What is all-wheel drive?
To put it simply, all-wheel drive systems can power both the front and rear wheels of a vehicle at the same time, compared to front- or rear-wheel drive vehicles that can only power either the front or rear wheels, respectively. There are full-time and part-time all-wheel drive systems available, which do have some differences in the way they work.
Full-time all-wheel drive powers all the wheels, all the time. Part-time all-wheel drive operates as either front- or rear-wheel drive most of the time, and can send power to the other wheels when necessary, as controlled by the vehicle’s traction control system. Both systems can use a series of differentials, couplings, and/or clutches to distribute the power to all four wheels.
How does all-wheel drive work?
Full-time and part-time all-wheel drive systems typically work without any additional input from the driver, making them easy to use in a variety of driving conditions. The vehicle’s sensors determine how much power is needed at each of the wheels to maintain traction and adjust accordingly. There may be some settings available for adjusting how the system works in driving conditions like snow or mud, but that is typically optional for everyday usage.
How is it different from four-wheel drive?
Four-wheel drive is found more often in larger trucks and off-road vehicles and is generally a system that can be turned on or off. There is typically different gearing selectable for high- and low-range, giving four-wheel drive vehicles maximum traction at a variety of speeds. Four-wheel drive systems deliver their power through front, rear, and center differentials, transfer cases, and couplings, which are heavier and can impact fuel economy more than all-wheel drive systems.
Do I need a vehicle with all-wheel drive?
If you live somewhere that experiences a variety of road and weather conditions like snow, ice, and mud, all-wheel drive may be an excellent choice when shopping for your next vehicle. These systems work automatically and can provide an extra sense of security for many drivers. Some things to take into consideration are the increased cost of adding all-wheel drive as an option for some vehicles, and typically a small reduction in fuel economy. And if you are planning to do some serious off-roading off the beaten path, a four-wheel drive vehicle will likely be a better option.
