4-wheel drive (4WD) and all-wheel drive (AWD) are often used interchangeably. However, they are very different systems. Do you know the difference between the two? If not, keep reading!
Many vehicles these days are propelled by only one axle, or two tires, either the front or the rear. 4WD, or 4×4, runs in complement with this two-wheel drive system. 4WD has to be put into use by the driver, often with a simple push of a button. Once 4WD is in operation, the drivetrain is split evenly, ensuring that the vehicle does not get stuck or spin out in bad driving conditions. Maximum power is sent to each wheel. The difficulty with 4WD is when it comes to turning the vehicle. Turning requires that the tires turn at different speeds, something that 4WD does not allow for. If you’re driving in suitable 4WD (icy roads, uneven conditions, loose dirt or gravel), that allows for the wheels to become unstuck and release their windup. Otherwise, they may lock up, especially when driving slow. The advantage to having to turn on the 4WD system is when it comes to gas mileage. Because these vehicles can operate in two-wheel drive mode for the most part, fuel economy is greatly improved.
AWD is a more modern invention for dealing with bad driving conditions. This system also splits the power from the engine between the two axles, but there are two main differentiators from 4WD. With AWD, the system is basically always on. There is no switch or button that needs to be touched to turn on the system. This means that when you hit unexpected road conditions, the system automatically kicks in to give you better traction and handling. Also, there is not always an even split between the axles. The system is constantly receiving feedback from the tires and then sending the most power to the wheels that have the most traction at the moment.
We hope this clears up any confusion you may have had about the two systems!