All-wheel drive (AWD) is one of the four basic types of drivetrains, along with front-wheel drive (FWD), rear-wheel drive (RWD), and four-wheel drive (4WD). Many people mistakenly believe that AWD and 4WD are the same—after all, doesn’t a car have four wheels? However, there are key differences in the way the two drivetrain systems function. AWD distributes varying amounts of torque to each of a vehicle’s axles, while 4WD sends a consistent, fixed degree of power to each axle.
While this explains the differences between these two systems, the real question is how each impacts the driving experience. Learn more about driving with 4WD vs AWD, as well as the advantages of the standard Subaru Symmetrical All-Wheel Drive system.
Understanding all-wheel drive (AWD) means understanding what a drivetrain system is. The drivetrain of any vehicle is a set of components and functions that send power and torque from the engine through the transmission. This process delivers power and torque to the wheels, enabling the vehicle to move. The type of drivetrain system in a car indicates which wheels receive power directly (the drive wheels), and how it is delivered.
In a car with AWD, all four wheels receive the proper amount of power directly, utilizing a front, rear, and center differential. This means that the wheels maintain the most consistent traction regardless of road and weather conditions.
AWD may include two types of all-wheel drive systems: part-time AWD or full-time AWD.
Cars with part-time AWD operate as either FWD or RWD vehicles under normal driving conditions. This means that only the front or rear axle receives power and engine torque at a given time. The system only automatically delivers engine power to the other axle when sensors detect slippage or a need for extra traction. Part-time AWD is also sometimes known as on-demand AWD.
On the other hand, full-time AWD systems deliver some degree of power and engine torque to both axles (and, therefore, all four wheels) at all times. Sensors constantly monitor traction and wheel grip, delivering power in proportion to the wheels’ needs. Most Subaru vehicles are equipped with a full-time AWD drivetrain.
Even among other full-time AWD systems, the innovative Subaru Symmetrical All-Wheel Drive stands out. Designed to emphasize balance, predictability, and optimized power distribution, Subaru Symmetrical AWD offers enhanced stability, traction, and control. The system is responsive in the face of icy surfaces, intense weather, and other dangerous road conditions. Here’s how standard Symmetrical AWD works to provide optimum safety when driving:
Like AWD, 4-wheel drive (sometimes called 4x4) systems send power to all four drive wheels. But the two systems operate with significant differences and involve the driver in different ways. Unlike all-wheel drive, 4-wheel drive typically offers two modes that drivers can shift between—high range for normal driving conditions and low range for particularly challenging terrain.
AWD continually works to keep the driver safe and in control. Conversely, 4WD is not an automatic, constant state but a mode that drivers must shift into. Without 4WD engaged, most vehicles with 4x4 capability operate in rear-wheel drive (RWD).
While AWD automatically varies among front, rear, and center differentials depending on needs, 4WD is typically paired with locked differentials. This means that both wheels on an axle are locked together, and all wheels receive power equally. All wheels in 4WD rotate at the same speed, regardless of which one requires extra traction. This can be useful when drivers find themselves stuck in snow, mud, or rocky terrain and need an extra jolt to free their vehicle. This is also true of AWD, which offers added traction by sending power to all wheels in muddy, sandy, or icy conditions.
No, they are not the same. While both drivetrain systems deliver power and torque to all four wheels, power is delivered in different proportions and at different rates in 4WD vs AWD.
AWD uses advanced sensors and technology to provide continuous AWD performance. This process ensures the right amount of power is delivered where it is needed most at any given time. By contrast, drivers shift into 4WD when they encounter a condition or hazard that requires extra overall performance and power.
While many people consider 4WD vehicles to be made for off-roading, they require the driver to engage 4WD in order to reap their full benefit. Subaru X-MODE® technology operates in a similar fashion for off-roading, but can be activated with the touch of a button as opposed to having to shift-down manually.
Conversely, Subaru Symmetrical AWD is engaged at all times without any extra action required by the driver. For instance, the Subaru Wilderness models are built for adventure enthusiasts who enjoy off-road driving. These models offer additional accommodations, such as extra ground clearance (at least 9 inches) and enhanced dual-function X-MODE for off-roading.
Generally, AWD offers superior performance over 4WD in inclement weather. Through rain, ice, or snow, AWD works automatically and nonstop to provide ultimate traction and stability without requiring additional action by the driver. This allows drivers to better focus on the immediate road conditions, while their car automatically adjusts to help maintain safety. In order to achieve the best possible performance in winter weather, both AWD and 4WD cars should be equipped with snow tires.
The 4WD Low setting enhances a vehicle’s traction by turning the wheels slowly, providing more torque. It can be used to offer more traction on rocky terrain, deep sand, and when traveling steep inclines.
The 4WD High setting delivers power to all four wheels, giving drivers the ability to handle icy or slippery road conditions while still traveling at normal speeds on city streets or highways – typically below 55 MPH.
Yes and no. Technically, the term 4x4 can apply to any vehicle where the engine transmits power to all four wheels. However, 4x4 is more accurately applied to AWD systems, which deliver torque to individual tires to improve traction.