What does 4x4 on a car mean?

[EstherLynn]

4x4 on a car represents the following meaning: 4x4 on a car indicates the number of wheels x the number of drives. The number before x represents the number of wheels of the car, and the number after x represents the number of drives of the car, so 4x4 means a four-wheel drive vehicle with 4 wheels. The extension of four-wheel drive vehicles with 4 wheels is as follows: The 4-wheel drive device on a car is a constant meshing type, adding a viscous coupler, eliminating the manual power divider, and automatically distributing the torque to the front and rear wheels as needed. On normal road surfaces, the 4-wheel drive device distributes 92% of the engine output torque to the front wheels and 8% to the rear wheels; on slippery road surfaces, at least 40% of the engine output torque is allocated to the rear wheels. When the front wheels start to slip, the speed difference between the front and rear wheels will immediately thicken the viscous fluid in the coupler and lock the coupler, so that the drive shaft only transmits torque to the rear wheels. When the speed difference between the front and rear wheels disappears, it will automatically return to the original drive form.