You might not know it, but most modern passenger cars equipped with all-wheel drive rely heavily on traction control systems to work properly. Why? Because they usually aren't equipped with locking differentials.
No matter how much power your car has, if it has an open diff, it's going to send power to the path of least resistance: the tire without grip. Today's traction control systems use wheel speed sensors to detect when one wheel is spinning disproportionately with another, and cut power or apply the brakes to distribute force to the other wheels without having to fall back on a mechanical locking differential. Wyatt Knox of highlights how the systems work in his latest video:
Using both two-wheel drive and all-wheel drive cars, he ties them to a stationary object and has someone drive on ice to see which wheels start spinning. Depending on the car and its onboard tech, one wheel, two wheels, three wheels, or all four wheels could spin. It's interesting to see how the cars distribute power, and we recommend watching if you'd like to learn a thing or two about how cars actually work.