AWD versus 4WD

Which is right for you?

As luxury pickup trucks and SUVs have grown tremendously in popularity, over 50 percent of all new vehicles sold in North America come with either all-wheel drive (AWD) or four-wheel drive (4WD). But what’s the difference between the two, and which is right for your needs? Well, this depends entirely on how you intend to use your sedan, SUV, or pickup. Let’s begin by learning a bit about the difference between all-wheel drive and four-wheel drive.

Four Wheelin’

The purpose for both AWD and 4Wd is to give you better traction. Today, lots of sedans, crossovers, and SUVs offer all-wheel drive to help you maneuver more confidently in snow, rain, or mud. AWD is generally designed more for road use, and doesn’t require manually engaging different gears or modes – it automatically gets power to the correct wheels when needed on the street.

Think of 4WD as bigger, beefier, and designed more for off-road situations. As such, 4WD comes into play in big pickup trucks, SUVs, or adventure vehicles like a Jeep. 4WD, which often is engaged manually with a lever or a switch, allows you traverse difficult off-road terrain – we’re talking about fording streams and rock climbing. For instance, the Ford Bronco has various 4WD modes that you can choose, called “GOAT” (Goes Over Any Terrain) modes.

Technically Speaking

Some people will tell you that all-wheel drive, four-wheel drive and 4×4 all means the same thing. Not so, from a technical point of view. There are differences. From the engine, you either pass through a torque converter or clutch, depending on whether the vehicle has an automatic or manual transmission. In an AWD system, there is a center differential. In a 4WD system, there is a selectable transfer case that passes to the rear differential. When engaged, the transfer case will also send power to the forward differential. However, in AWD systems the center differential will automatically send power to one or both of the axles all the time – a clutch pack will directs the torque to where it is needed.

The big difference is that in AWD, the driver is not choosing where the power is sent. The system monitors road and driving conditions and sends power to where it is needed most. On the other hand, 4WD systems allow the driver to decide where to send the torque by using the transfer case to choose specific driving modes for front-wheel, rear-wheel, or four-wheel drive applications.

All-Wheel Drive

As indicated in the naming convention, all-wheel drive systems provide power and traction automatically to the front and rear wheels of a vehicle. Standard cars come with rear-wheel drive or front-wheel drive, but all-wheel drive can power all of the wheels to offer better grip on the road when you need it most – like when cornering in the snow.

There are two kinds of AWD: full-time and part-time. Full-time AWD powers all four wheels at the same time, and part-time AWD switches the traction to wheels that need more power only when needed. Both of these AWD systems operate on their own, with no input from the driver. The proper amount of torque is sent to the proper wheels by a series of differentials, couplings, and clutches to deliver the best possible traction. In other words, AWD works seamlessly from the driver’s point of view. The system automatically applies traction where needed on wet or slushy roads.

All-Wheel Does the Thinking for You

A vehicle with full-time AWD uses both front and rear axles at all times for better handling on dry pavement as well as under slippery conditions. Part-time AWD only sends torque to two driven wheels under normal conditions. Using electronic sensors, the system can then automatically engage all four wheels to control the amount of power needed to each wheel when extra traction is required.

The great thing about AWD systems is that they do the thinking for you. Either all of the wheels are being driven at all times, or the system sends power where it is needed when it senses a loss of traction. You can find AWD offered on a lot of different vehicles.  AWD is available or standard on the Dodge Challenger and Charger, the Subaru Crosstrek, Outback and Legacy as well as such diverse vehicles as the Fiat 500X, the Lincoln MKZ, and the Ford Fusion. Many high performance vehicles like the BMW M5, Mercedes-AMG models, and many Porsche models also have highly sophisticated AWD.

AWD works in a range of conditions including rain and snow, even including some light off-roading. But when you are talking about traversing a desert, climbing a craggy mountain, going where the only path is through knee-deep mud, or crossing a river, you’re into four-wheel drive territory.

Four-Wheel Drive

If this article were written by comedian Tim Allen, this is where he would make those delightful chimp grunting noises. Were it penned by Jeremy Clarkson, he would no doubt shout, “More power!” Four-wheel drive trucks and SUVs use a series of front, center, and rear differentials along with transfer cases and couplings to provide torque to all four wheels.

Today’s 4WD systems are incredibly sophisticated, allowing you to engage or disengage your 4WD by way of buttons, mode selectors and levers. Much like AWD systems, 4WD is designed to send torque to all four wheels to increase traction where needed. But while AWD will get the job done for typical highway travel, 4WD is needed for heavy lifting. For that reason, 4WD systems are generally much more robust and built to last when handling the toughest terrain.

Many 4WD systems allow the driver to select various settings, from mild to extremely wild. Low and high ranges give you the proper traction in various conditions. Low settings are best for maximum traction off-road, while high settings are more useful for snow, gravel, or loose sand.

Just as with AWD, 4WD is available in full-time or part-time variations. With a full-time system, all four wheels receive traction all the time whereas a part-time system is designed to handle more extreme conditions. Part-time 4WD lets you drive using only two wheels until four are needed, and then to engage 4WD via button or lever in order to get the traction where it matters. Some of these systems let the driver lock the differentials for extra traction in extreme conditions.

Sophisticated 4WD systems are available for almost any off-road application, often paired with heavy-duty suspension packages, underbody shielding and meaty off-road ready tires. As mentioned at the start of this article, your decision to buy a vehicle equipped with either AWD or 4WD comes down to how you plan on using the car, truck, or SUV.

The Wrap Up

Whether you are driving an all-wheel drive sedan or a fully decked out 4×4 truck, there is always a limit to what technology can provide when it comes to traction and grip. You can go beyond the limits of what your vehicle can provide under extreme conditions.

Road conditions combined with the speed you are going and the grip provided by your tires all add up to how well you can engage traction on snowy, wet roads. All this comes into play when you are trying to brake as well.

Your needs for an AWD or 4WD vehicle depend largely on where you live and how you intend to use your vehicle. For sedans, crossovers and SUVs that are being used in areas of the country where road conditions may change quickly due to snow and ice, AWD might be best for you. However, if you have to traverse deep snow and more extreme off-road conditions, 4WD is better to handle snow drifts and icy hillsides. And remember: for driving in winter conditions, AWD or 4WD may help you get going, but they won’t help you stop; make sure to invest in a good set of winter tires!

Let Lithia Help

No matter what kind of car, truck or SUV you’re interested in, Lithia Motors has a dealership near you and we’ll get you into the vehicle of your dreams. Have questions about AWD or 4WD? We’re here from you.

Lithia Canada 44.0486481, -79.4266966.