What Is The Difference Between AWD and 4WD?

When it comes to purchasing a vehicle, one of the most common questions you will get asked is whether you want a vehicle that has four-wheel drive or all-wheel drive. These two systems are called drive-train systems, which determine how and when torque is supplied to your wheels. Choosing the correct system for your vehicle use is important as each will perform differently in various environments. In this article, we are going to explore the differences between how four-wheel drive vehicles and all-wheel drive vehicles work, which one you should buy, and what the pros and cons of each are.

What Is All-Wheel Drive and How Is It Different Than 4WD?

Despite the fact that four-wheel drive and all-wheel drive are often used interchangeably in both sales literature and in-vehicle advertising, they are indeed quite different. First off, four-wheel drive is a manual mode that you have to select and turn on either by pressing a button, pulling a lever, or turning a dial. When you select the 4WD mode, the power from the drive-train gets split equally between the front and rear axles ensuring that the vehicle does not spin out or get stuck on or in touch terrain. When the power gets split equally to both the front and rear drive shafts, the tires remain spinning at the same speed. In addition to this, some of these systems will have what is called “locking axles” which keep all four wheels in a turning motion regardless of whether they have traction or not. This is what allows trucks and off-road SUVs to have a tire or two up in the air and spinning while the remaining tires hold traction on the ground.

More modern four-wheel drive systems can either be full-time or part-time. A full-time four-wheel drive system will always be engaged where it will automatically switch between two and four-wheel-drive mode, whereas part-time, requires the driver to switch the mode manually.

While all-wheel drive also splits the power from the engine between the front and rear axles, the newer technology does have some key differences to it in that it is always on and in that the power isn’t always evenly distributed to the tires. A vehicle that has AWD will never have to turn on a mode as the system will automatically kick in when you encounter unexpected road conditions. Beyond this, since the all-wheel-drive system is continually gaining feedback from the tires, the power range between the front and rear axles will not always be split evenly. Rather, the system will send the most power to the wheels which have the most traction.

What Are The Pros and Cons of AWD and 4WD?

For the all-wheel-drive, you will have increased control and grip in unexpected road conditions, is reliable because it is controlled with a computer and sensors (better safety rating), and will give you sportier handling and traction in a larger variety of vehicles. The positives for four-wheel drive include giving you the best traction in off-road conditions, is durable and rugged and is fuel efficient as it can be switched off when unneeded.

Four-wheel drive is not suitable for all driving conditions, however, and cannot be driven on pavement. Plus, they are more expensive than two-wheel drive-trains and will add more weight and complexity to the vehicle. As for all-wheel-drive systems, they are not suitable for extreme off-road conditions and are not as good on fuel.

Which System Should You Buy?

If you are planning on conquering tough terrain, you go with a four-wheel drive vehicle, but if you live in an area that has bad weather conditions such as snow and rain, and you aren’t planning on off-roading, you should go with an all-wheel-drive system.