AWD vs. 4WD: What’s the Difference?
What you need to know about all-wheel drive and four-wheel drive
If you find yourself asking what the difference between four-wheel drive and all-wheel drive is, don’t feel bad. It can get confusing. What it boils down to is whether or not the vehicle has a multi-speed transfer case. A transfer case is effectively a second gearbox, usually mounted behind the transmission, that allows drivers to select a mechanically lower gear, which aids off-road driving by multiplying torque and increasing control on ascents and descents.
Most all-wheel-drive vehicles won’t have a selectable low range, but many four-wheel-drive vehicles use what’s known as “full-time” four-wheel drive. This means they always drive all four wheels while still having a selectable low range. Other four-wheel-drive vehicles will spend most of their time in two-wheel drive and require the operator to select four-wheel drive manually. This approach was the most common design for many years and is still in use today in many trucks.
Some all-wheel-drive vehicles can also choose to drive either just the front or rear wheels, depending on how the vehicle was engineered. But many, like Subarus, will constantly drive all four wheels, adjusting the bias of engine torque sent to each axle to suit road conditions.
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