How Does All-Wheel Drive Work?by Ted Marten
An all-wheel drive system is made up of the front and rear differentials and the transfer case. They work in combination to make an all-wheel drive system work. All-wheel drive systems allow your vehicle to receive torque from the engine simultaneously. This gives you more control over your vehicle and gives you a smoother drive on different types of driving surfaces.
The differentials are located between the front two wheels and the back two wheels. Their job is to transfer torque from the drive shaft to the drive wheels. An all-wheel drive system helps your cars make turns because the differentials allow the wheels on your vehicle to travel at different speeds. The inside wheels and outside wheels of your vehicle takes different paths during a turn, and having them travel at different speeds makes your vehicle work more efficiently and effectively.
The transfer case in the all-wheel drive system splits the power between the front and rear axles. The transfer case helps make the all-wheel drive system work by containing a devise that allows speed changes between the front wheel and the back wheels. The viscous coupling allows the wheels to function on any type of surface. The viscous coupling consists of two plates that are filled with a thick fluid. This transfers torque to the wheels so that they don't spin uncontrollably on a slick surface.