Wheel formula

2.2.1 Wheel Arrangement 

While reading any specialized publications, you can often come across the concept of "wheel arrangement". This simple phrase conceals a brief description of the scheme of distribution of the thrust from the engine between the wheels. Two digits are indicated in order to display the wheel arrangement, for example, "4 × 2". The first digit indicates the total number of wheels on the car (if the wheel is paired, then it is counted as one), and the second digit - the number of drive wheels, that is, wheels to which rotation, thrust or torque is transmitted from the engine (for more details on this concept, see the "Engine" chapter). 

So, for example, if it is written that the wheel arrangement is “4 × 2” (read: “Four by two”), it means that the car has 4 wheels and 2 of them are drive wheels. If it is indicated as “4 × 4”, then the thrust from the engine is transmitted to all wheels of the car.