AWD is Not 4WD
The words “all-wheel drive” and “four-wheel drive” are sometimes used interchangeably, although they are not. There are significant distinctions between the two. Perhaps you’ve never recognized the difference between all-wheel drive and four-wheel drive and were too scared to speak, or you didn’t understand they meant different things.
In fact, an all-wheel-drive system may deliver a varying amount of torque to each axle, and the driver generally has no control over this. A four-wheel-drive system provides a constant amount of power to each axle and may be turned on or off by the driver. So, how do they go about carrying out their duties? An all-wheel-drive system, in general, employs a central differential to distribute engine torque between the two wheels. In contrast, a four-wheel drive depends on a transfer case, which operates similarly to a locked differential.
You may be asking why both of these systems are required at this stage, given that the goal of both is to distribute power to all four wheels. Because the system provides a constant amount of power to each tire, four-wheel drive is ideal for off-roading and other low-traction conditions. Whichever tire has the best traction will receive the necessary power, preventing the car from being stuck.
However, the four-wheel-drive doesn’t always function on the road for the same reason it works so well off the road. A car’s wheels spin at different rates when it turns a corner. When four-wheel drive is enabled, the system attempts to make each wheel spin at a comparable pace, making on-road driving difficult. As a result, most four-wheel-drive systems may be used in two-wheel drive mode, which is recommended for road use.
All-wheel-drive systems are ideal for highway use since they actively direct power to the wheel (or wheels) that require the most. Some all-wheel-drive systems feature a set torque distribution between the front and rear axles, but since they use a differential rather than a transfer case, they don’t have the same cornering difficulties as four-wheel-drive systems.