All-wheel drive: what it means, how it works and the best models

All-wheel drive. It's a term that you've probably seen quite a bit while shopping around for cars and, of course, here on Kijiji Autos. While most road-going cars tend to be front-wheel drive—meaning the engine's power hits the road through the front wheels only—all-wheel drive (AWD) cars transmit power to all four corners. We're here to tell you the pros and cons of the system—and whether you need it in Canada.

How does all-wheel drive work?

We have to start with one important fact: Not every all-wheel drive system is the same. Each manufacturer has its own version—sometimes even more than one! But the main thing to look out for when choosing an AWD system is whether it’s on-demand or permanent.

On-demand systems have the ability to switch between two-wheel drive and all-wheel. While older cars tended to leave this up to the driver, newer cars can shuffle the power automatically, using a range of sensors to determine where a slip is happening and where power needs to go.

Permanent all-wheel drive will always split the engine’s power between the front and rear axle. This has its benefits: one major one is that it doesn’t rely on wheels slipping at one end of the car before sending power to the other one. However, permanent all-wheel drive has the significant drawback of increased fuel consumption.

Is all-wheel drive safer? Yes, because it provides optimal grip during more driving conditions, especially when dealing with slippery or uneven surfaces.

All-wheel drive, four-wheel drive or 4×4?

If you’ve seen one of these terms, you’ve probably seen the others too. That’s because, for all intents and purposes, there is no difference between all-wheel drive and four-wheel drive (4WD).

Traditionally, more off-road-ready vehicles like Jeeps come with four-wheel drive systems. A true four-wheel drive system offers a transfer case, which provides maximum torque (turning power) at low-speed situations.

On the other hand, modern-day active all-wheel drive systems have closed much of the gap, with advanced computer systems capable of determining which individual wheel needs power most.

Nearly every SUV on the market offers either of these systems as options. Check out our SUV buyer’s guide for even more info on what to look for.

Do I need all-wheel drive over front-wheel drive?

Say you’re looking at a modern crossover. You’ve got two options for drivetrains: front-wheel drive or the (slightly more expensive) all-wheel drive. Why buy all-wheel drive?

For starters, it’s safer. All other things being equal, an AWD car will keep you out of trouble more than a 2WD car because it can provide optimal traction more of the time. This makes it better for winter driving, too—though nothing beats fitting proper winter tires. Don’t miss our full list of important winter safety features.

If you do most of your driving in a big city, with plenty of plowed roads, front-wheel drive may suffice. A more rural location may require the extra grip and ride height of an AWD option, though. You’ll want to consider that if you do regular towing, too.

What are the best all-wheel drive models?

With so many AWD models on the market, it’s hard to pinpoint the best. We’ve picked two from different ends of the market to show the diversity on offer.

Certain trim levels of the , including the LE, XLE and Adventure, offer sophisticated all-wheel drive systems with special off-road capabilities. These upgraded drive modes are designed for the commuter with a longing for riding on challenging terrain.

A brand known for its Super Handling All-Wheel Drive (SH-AWD) is Acura. Great for the city, the

distributes energy smartly, sending 90% power to the front wheels during straight driving, and then transferring 45% to the rear wheels during acceleration. This saves fuel—but the system can also send the majority of its power to the rear wheels if conditions require it.

Now you’re up to speed on these unique takes on all-wheel drive, browse the Toyota Rav4 and Acura RSX on Kijiji Autos.