Design features of all-wheel drive vehicles widely used in the national economy of our country, the basics of their theory, analysis of traffic and operation conditions, ways to increase efficiency are described. Significant attention is paid to fuel efficiency, safety, controllability. In the second edition (1st ed. 1981) contains many practical recommendations for determining general parameters and characteristics, improving the efficiency of using four-wheel drive cars, and provides modern research and testing methodology. For engineers involved in the design, engineering, calculation and operation of vehicles.