AWD vs. 4WD: The Difference Between All-Wheel Drive & Four-Wheel Drive (4x4)

When shopping for a vehicle with enhanced grip, control, safety, and capability, you’re likely browsing models that put the power down at all four corners: AWD (all-wheel drive) and 4WD (four-wheel drive).

For everyday use, occasional trailheads, and high-speed control in an agile and efficient package, go with AWD. For off-road capability, towing, and heavy-duty work, a truck-based four-wheel drive might make more sense.

What’s really the difference between all-wheel drive (AWD) and four-wheel drive (4x4, 4WD)? AWD tends to indicate an always-on system using a differential to variably split power, while 4x4 systems rely on a manually activated transfer case to connect all four wheels equally for better off-road and low-speed traction.

Let’s dig into these systems a bit deeper. But first, refresh yourself on the standard systems: front-wheel drive (FWD) and rear-wheel drive (RWD).

When thinking of the traditional powertrain layout of a car, you might be visualizing an engine at the front with a driveshaft running to the rear axle, including the differential and wheels.

The main benefit of rear-wheel drive is that it splits the key duties of motion. While the rear wheels provide power, the front wheels do the turning. Yet, while this simple, straightforward layout works in most cases and can handle plenty of power, they require space for a driveshaft. That results in either a hump in the cab running front-to-back or a high-riding vehicle with the heavy driveshaft underneath.

Front-wheel drive powertrain layouts weren't quite optimized until the ‘70s and ‘80s. A FWD powertrain turns the engine (and transmission) sideways, connecting to one of the front wheels through a constant velocity (CV) joint.

FWD cars give the front wheels both jobs: steering and powering. However, with a more compact layout, they tend to weigh less. Plus, with no driveshaft to package, the car can be smaller, lower, and more spacious inside. Eventually, most cars have taken on a FWD layout for their fuel efficiency and packaging benefits, although they are not best-suited for heavy-duty applications like towing.

While FWD cars will understeer (turn wider than intended) when they lose grip, RWD cars will oversteer (turn tighter than intended). Those exact conditions are why many drivers look for a vehicle with more precise power delivery, like an AWD or 4x4 option.

Using real-time data from sensors throughout the drivetrain, Mitsubishi Motors' Super All-Wheel Control (S-AWC) actively adjusts the power balance between wheels for maximum traction and control. It constantly optimizes the AWD system to keep the driving experience predictable, comfortable, and confident.

To get technical, S-AWC uses torque vectoring with an advanced and efficient brake-based system for immediate responses to inputs and conditions.

The possibilities for advanced safety, handling, and performance are even greater when the powertrain is electrified. In the Outlander PHEV, a fast-charging plug-in hybrid, the S-AWC system deploys the instantly responsive torque of electric motors to the AWD formula. Not only upping efficiency, Canada’s best-selling PHEV’s Super All-Wheel Control helps it drive comfortably in slippery conditions and put its power down with excitement and agility.

Among Mitsubishi Motors’ many acclaimed driving technologies, S-AWC brings competitive all-wheel control, safety, and performance to quick, stylish, and functional SUVs. Motor Trend calls the Outlander’s S-AWC snowy handling “quick and immediate” and categorizes the advanced AWD SUV as “a truly capable winter driver” in comparison to other similar AWD hybrids without S-AWC.

At the other end of the all-wheel performance spectrum are four-wheel drive systems, which trade responsiveness, efficiency, and customization for towing, working, and extreme off-roading applications.

Four-wheel drive, also called 4x4 (four-by-four) and 4WD, uses a transfer case to turn a rear-wheel drive platform into one that can also power the front wheels. It’s a system mostly used on trucks and other heavier-duty body-on-frame vehicles like full-size SUVs and off-roaders.

If you’re looking for a vehicle that can crawl up the side of a rocky hill, drive down a snowy trail into the woods, or tow a load along a slippery gravel road, a 4x4 is an ideal choice. They tend to be bigger, stronger, and actuated only when needed by a manual button or lever connected to the transfer case and low-range gears.

What are the transfer case and low-range gears on a 4x4?

Recalling how a differential in an AWD system uses gears to transfer power variably to each wheels, a 4x4 system is both simpler yet more robust. While less ideal in on-road or twisty conditions, they excel on loose terrain and hold up to the forces of towing and other heavy duties. The four-wheel drive transfer case is usually engaged manually with a lever or button but is sometimes automatic.

The transfer case connects the 4x4’s rear driveshaft directly to its front driveshaft so that all four wheels receive an even split of the engine’s power. However, a disadvantage of 4WD is that it can experience wheel hop or driveline binding on pavement when 4WD mode is engaged.

Without some tolerance, or slip, on the road surface, 4WD has some problematic handling characteristics due to the wheels spinning equally as fast at all four corners, instead of varying to suit curves. This is most often experienced in tight parking lots or city streets. However, simply disengaging 4WD and running in 2WD only usually solves the problem.

Many 4WD systems include a low-range gear. Low-range four-wheel drive, AKA “four low” or 4L, adds an additional gear in the transfer case that turns slower — which allows the vehicle to crawl slowly forward. When stuck in the snow, climbing rocks, or taking off with a heavy load in a muddy lot, that helps the truck maximize its available torque.

Typically only available on trucks and truck-based SUVs, 4x4 is the choice for more rugged environments. Being stronger means heavier, however, and usually more powerful, which leads to worse fuel economy compared to AWD, FWD, and RWD vehicles.

While both systems slightly reduce a car’s fuel efficiency rating, AWD cars tend to be more fuel efficient. Partly, that’s because they tend to be based on more fuel-efficient FWD cars to begin with. Plus, the differential and related components are lighter and easier to package than a 4x4’s heavier and more cumbersome transfer case and driveshafts.

Another noticeable difference is how the systems kick in. AWD is typically automatic, meaning it engages when it senses a loss of traction. Or, it’s a full-time AWD system that always has all four wheels engaged. A 4WD vehicle usually requires the driver to move a lever or push a button to engage the front driveshaft. It’s then locked in 4x4 mode until moved back into 2WD position.

Perhaps most important is how AWD and 4WD systems behave on the road. AWD systems do well to keep traction at everyday speeds on slippery surfaces like snow, ice, gravel, or mud. They also help a car launch off the line quickly and hold corners at higher speeds. That’s why AWD is common not just in all-weather vehicles but also in sports cars.

A 4x4 is geared more to lower-speed situations and might be kept in 2WD mode on city streets and highways. But when the road gets really rough, a 4x4 can crawl over and out of more obstacles while holding up to the abuse. It can also force tons of power through its simpler, more robust mechanics, keeping up with the demands of off-road towing, for instance. They also often offer low-range gearing for even better capability.

AWD systems tend to be more complex, especially if they include advanced features like lockers and additional traction sensors. That can also be more expensive to maintain and repair than a 4WD vehicle’s basic transfer case setup. However, 4WD systems are usually found on trucks and heavier-duty vehicles, which tend to have a higher starting price than passenger vehicles. Meanwhile, even some of the lowest-cost economy cars can be optioned with AWD.