In the US, crossover utility vehicles, or CUVs, are the best-selling light-duty vehicles on the market, even eclipsing sedans and hatchbacks. Crossovers are spacious, comfortable, and have high seating positions which give good views of the road, all the while not sacrificing too much in terms of handling characteristics or fuel economy.
When shopping for one (or even trucks and SUVs, too), you’ll likely hear the terms “all-wheel drive” or “AWD” mentioned. All-wheel drive is a popular drivetrain option which allows power to be sent not only to the front wheels, but to the rear wheels as well. Check out our front-wheel drive versus rear-wheel drive versus all-wheel drive comparison to learn more!
If you’ve heard of all-wheel drive, have you ever heard about four-wheel drive? While it sounds similar (and even works similarly), these are two distinct drivetrain systems, each with their own distinct advantages and disadvantages.
Dealerships and private sellers may use the terms interchangeably, but strictly speaking, it isn’t correct to do so because of these mechanical differences. If you’re in the market for a crossover, SUV, or truck, it’s important to understand the differences so that you can be satisfied with your purchase by knowing exactly what you’re buying. Let’s take a closer look.
ALL-WHEEL DRIVE
As the name suggests, an all-wheel drive drivetrain means power can be sent to all the wheels (how clever). This is in contrast to front-wheel drive, which is commonly available with sedans, hatchbacks, and station wagons, and rear-wheel drive, which is more common on sports cars and hot hatches.
If front-wheel drive can suffice for most vehicles other than crossovers and SUVs, you might be asking yourself, “What’s the point of AWD?”
Although AWD systems add weight and complexity to the drivetrain, they excel in one key aspect: control under heavy rain or snow. All-wheel drive systems have a traction advantage on wet, loose, and frozen surfaces. In particularly snowy climates, an AWD vehicle equipped with a good set of snow tires is even more capable.
This results in less stress when driving under these conditions and could even result in a safer journey in extreme circumstances. Teen drivers—or inexperienced drivers in general—may feel safer when driving with AWD under these conditions.
FOUR-WHEEL DRIVE
Just like all-wheel drive powertrains, four-wheel drive vehicles send power to all (four) wheels. The key differences lie in how this power is distributed to the wheels.
Although AWD vehicles send a variable amount of torque to the rear wheels, the driver typically can’t control this. In contrast, 4WD vehicles send a fixed amount of power to the rear wheels, and the driver has the power to switch this on or off.
Vehicles equipped with AWD generally use a center differential (a component of the drivetrain which splits the engine torque two ways) to distribute torque between the two axles. 4WD-equipped vehicles instead generally use a transfer case, a component that essentially functions as a locking differential, “locking” both wheels on an axle together.
4WD is common on off-road vehicles or those designed with off-road capabilities in mind. Since each tire receives a fixed amount of power, the tire with the most traction is assured to get the necessary power it needs to navigate harsh terrain. This also helps prevent the vehicle from getting stuck.
COMMUTING OR OFF-ROADING?
Almost half of the new vehicles sold in the US are equipped with either all-wheel drive or four-wheel drive. All-wheel drive is more popular than its cousin, however, and there are several reasons that could explain this.
In an AWD system, no input is necessary from the driver to control the drivetrain. The system controls power itself, automatically modulating torque and sending power to the necessary wheels, which is beneficial in dangerous situations such as a sudden loss of traction.
Plus, AWD is offered on a wide variety of vehicles, offering more flexibility versus the relatively smaller amount of 4WD offerings.
But what if you’re looking to do some serious off-roading? In that case, look no further than four-wheel drive. 4WD gives you the choice as to when to apply torque to the rear wheels, and these systems are designed for ruggedness and durability in unforgiving terrain.
While both systems have their merits, they’re best used under different circumstances. In a nutshell: if your next vehicle is going to be used for (on-road) commuting, you’ll probably be better off with AWD. If you’re going to be using your vehicle for some serious offroading, 4WD will be the better system for you.
Neither system is better than the other. Instead, they can both have their respective places in your garage. Comment below and let us know which of these drivetrains is better for you, and which one, AWD or 4WD, made its way into your own garage!
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