AWD vs. 4WD: What's the Difference?

"AWD vs. 4WD — what's the difference?" Few terminologies in the automotive lexicon cause such confusion as "all-wheel" drive (AWD) and "four-wheel" drive (4WD). And while there are some clear distinctions between the two, the difference is that an AWD system is typically best for giving a vehicle all-weather traction all the time, while a 4WD system is meant to be a little more rugged and capable on off-road terrain. This oversimplifies how the two drivetrains diverge, and our apologies to the engineers behind them, but it's a useful way to think about these often complex systems.

At one time, if you wanted a vehicle with four driven wheels, you were limited to just a handful of large trucks and full-size SUVs, most of which were used for work chores or off-road adventure. But times have changed. In fact, 61.5% of new vehicles sold in the U.S. as of May 2023 were equipped with either all-wheel drive (AWD) or four-wheel drive (4WD), according to Edmunds sales data. And among models that offered AWD or 4WD as an option, 64.2% of buyers chose to have their vehicles equipped, according to Edmunds.

The popularity of all-wheel-drive vehicles that can send power to both the front and rear wheels is indisputable. But the terminology gets more perplexing as AWD systems have become more robust and 4WD has gotten more advanced, blurring the lines between the two. Various manufacturers also use these terms differently, adding to the confusion.

To help answer everything about AWD vs. 4WD, we'll examine how each system works and the advantages and disadvantages of each. With this knowledge, you can make an informed decision when shopping for your next SUV, sedan, car or truck.

• What is all-wheel drive?
• How does all-wheel drive work?
• What are the disadvantages of AWD?
• What is four-wheel drive?
• How does four-wheel drive work?
• Four-wheel-drive pros and cons
• Is 4WD or AWD better in snow?
• Which is better: 4WD or AWD?

What is all-wheel drive?

As the name implies, all-wheel-drive systems power both the front and rear wheels all the time. But in practice, there are actually two types of drivetrains that are called AWD. One does, in fact, drive all the wheels continuously, and some manufacturers refer to this type of system as full-time AWD. The second, often called part-time AWD or automatic AWD, operates most of the time in either front-wheel drive or rear-wheel drive, depending on the vehicle's drive system. In these systems, power is delivered to all four corners only when additional traction control is needed.

How does all-wheel drive work?

Both full-time and part-time systems generally operate with no input from the driver, although some offer selectable modes that allow a degree of control over how much power goes where. All the wheels get torque through a series of differentials, viscous couplings and/or multi-plate clutches, which help distribute power to the wheels so that the car's traction is optimized. The vehicle still operates smoothly under routine conditions.

Full-time AWD: In full-time AWD, both the front and rear axles are driven all the time. On dry pavement, this kind of AWD can help the vehicle handle better and ensure that full power gets to the road. And in slippery conditions, such as ice, snow or mud, it provides always-ready traction for safer, more confident handling. Historically, a good example of full-time AWD was Audi's Quattro system, although in recent years the part-time Quattro Ultra variant has become more common in Audi's lineup because it's better on gas.

Part-time AWD: In normal operation, part-time AWD sends torque to two driven wheels, either the front or rear, depending on the make and model. The part-time system then automatically engages the other wheels when road conditions demand extra traction. Modern part-time AWD uses an array of electronic sensors that feed information to a computer, which controls the amount of power directed to each wheel. This setup is commonly found on car-based crossover SUVs and AWD cars.

What are the disadvantages of AWD?

So since all-wheel drive works in the background to deliver optimal traction, why wouldn't you car equipped with AWD? Well, first is cost. All-wheel drive requires more hardware and computing power, and it typically adds a few thousand dollars to the sticker price. AWD systems are also heavier and typically sap fuel economy by 1-3 mpg.

Finally, while AWD works well in a variety of conditions, from rain to snow to light off-roading, most systems are simply not robust enough to handle rough, uneven and slippery terrain. That means you're limited to how far you can venture into the muck without possibly getting stuck. While that AWD hatchback may seem hearty enough to get you to a distant campsite, you'll need to exercise caution.

For many drivers, though, the pros will outweigh the cons. The best thing about AWD is that the driver doesn't have to make any decisions about engaging the system. Either all the wheels are being driven full time, or the system itself is designed to sense a loss of traction and send power where it's needed.

AWD is also available on a wide variety of vehicles, from compact sedans to performance models to all sizes of SUVs, giving you a broad range of choices.

What is four-wheel drive?

This is the more traditional system that comes to mind when most people think of drivetrains that power all four of a vehicle's wheels. It isn't surprising since the principle goes back almost to the beginning of motorized transportation. The stereotypical picture of a 4WD vehicle is of a truck with high ground clearance, a shielded underbody, tow hooks and big, knobby tires. And it's true that this system is found primarily in trucks and truck-based SUVs.

But through the years, 4WD engineering has become increasingly sophisticated, and although it generally remains capable of more serious off-road use, it can now be found on a wider variety of comfortable, even luxurious models. 4WD systems deliver torque through a series of front, rear and center differentials, transfer cases and couplings, which allow the vehicle to operate at maximum traction under a variety of conditions.

How does four-wheel drive work?

Like AWD systems, 4WD is designed to maximize traction front and rear. But 4WD systems tend to be more robust than AWD ones and can generally handle more rugged terrain. And they, too, come in two types: full-time and part-time.

Traditional 4WD systems have a two-speed transfer case with high- and low-range modes that can be selected by the driver, either with an electronic switch or a mechanical lever. The low-range setting multiplies torque to provide superior control and grunt in low-speed off-road environments. The high-range setting is useful for less challenging off-road scenarios as well as slippery on-road conditions, such as packed snow, ice, loose sand or gravel.

Full-time four-wheel drive: Full-time 4WD operates as a full-time AWD system does, with all four wheels receiving power on a continuous basis. Late-model Toyota Land Cruisers are a good example — they send power to both the front and the rear by default, so there is no standard two-wheel-drive mode (unlike typical 4x4 trucks with their part-time systems), but there's also a selectable low range for the really tough off-road stuff. In some designs, the driver may have the additional option of controlling how power is apportioned to the front and rear axles through selectable modes and locking differentials.

Part-time four-wheel drive: This type is the real traditionalist of four-wheel propulsion and can most often be found in trucks and SUVs that are designed to work and play in extreme conditions. In this case, the vehicle is typically rear-wheel drive by default, so the four-wheel-drive system requires the driver to opt in by either pushing a button or shifting a lever. Locking center differentials are par for the course, but many part-time 4WD systems also allow the driver to lock the vehicle's rear differential, which ensures that both rear wheels get power no matter what. Hardcore setups let you lock the front differential, too — this is the hallowed "triple-locked" configuration that means you'll only get stuck if all four wheels have no traction.

Four-wheel-drive pros and cons

There's no substitute for true 4WD in tough off-road scenarios. Even though 4WD systems are now available in well-appointed luxury trucks and SUVs, at heart they are designed for ruggedness and maximum traction when you need it most, so they are the right choice for difficult terrain.

These days, 4WD design has become increasingly refined, as has the design of the vehicles that can be ordered with it. But depending on the make and model, 4WD vehicles often deliver a stiffer ride than their two-wheel-drive counterparts. These systems also have a detrimental effect on fuel economy and increase the initial cost of the vehicle.

Is 4WD or AWD better in snow?

A couple of things to keep in mind up front: Whether you choose AWD or 4WD, any vehicle can lose traction and spin out if pushed hard enough. And while both systems are designed to increase traction by engaging the front and rear wheels, neither helps you stop better in snow; winter tires do. Having said that, both AWD and 4WD can give you a significant advantage in snowy and icy conditions and may be worth the extra cost depending on where you live and how you use your vehicle.

Driving in cold weather often means encountering a variety of rapidly changing road surfaces, from soft snow to hard-packed snow to glare ice. AWD and full-time 4WD systems, which deliver power to all four wheels all the time or automatically engage four-wheel torque when needed, are best at dealing with these changing conditions. When paired with a good set of winter tires, AWD vehicles take the guesswork out of the equation and can act more quickly than a driver to handle variable road surfaces.

On the other hand, 4WD is generally well suited to navigating deeper snow or other more extreme winter conditions. It can get you unstuck from a snowdrift more easily, manage icy hills more effectively, and get you to work safely before the roads are plowed.

That said, numerous studies have shown that in order to maximize the full potential of AWD or 4WD in the snow, the vehicle needs to be equipped with a good set of winter tires. Similar studies have also shown that a front-wheel-drive vehicle equipped with winter tires can have its own strengths in the snow — it is less likely to experience oversteer, and its braking distances are comparable to those of an AWD vehicle in heavy braking.

Which is better: 4WD or AWD?

Not surprisingly, the answer to the AWD vs. 4WD debate is: It depends. More specifically, it depends on where you live and what kinds of driving conditions you encounter, as well as personal taste.

AWD can be found in cars, trucks and SUVs of all sizes, from compact to full-size, giving you the widest possible range of vehicles to choose from. It delivers increased traction in normal winter conditions or light off-roading and provides the fewest compromises in ride and fuel economy on dry roads. And it has the advantage of either continuously powering all four wheels or automatically controlling which corner gets the torque, taking the decision-making process out of the driver's hands.

But 4WD is still the better choice for those who need to work in extreme weather conditions or enjoy off-road adventuring. This system often comes in trucks and SUVs with higher ground clearance than average, making them well suited to managing deep snow, rocky terrain and steep grades, as well as carrying or towing heavy loads. In addition, the two-speed transfer case with low- and high-range gearing gives the driver the greatest amount of control over where and how the power is delivered, especially when paired with multiple locking differentials.