On the normal road surface, the four-wheel drive device distributes 92% of the engine output torque to the front wheels and 8% to the rear wheels; On wet roads, at least 40% of the engine output torque is distributed to the rear wheels; When the front wheel starts to slip, the speed difference between the front and rear wheels will immediately thicken the mucus in the coupling and lock the coupling, so that the transmission shaft only transmits torque to the rear wheel. When the speed difference between the front and rear wheels disappears, it will automatically return to the original driving form.
The front and rear wheels always maintain the four-wheel drive mode, and the engine output torque is set to 50: 50 for the front and rear wheels when driving. Full-time drive has good driving controllability and tracking performance, but the disadvantage is that it is more waste oil and less economical. If the road surface is bad or the driving wheels slip, the computer will automatically detect and immediately distribute the engine output torque to the other two wheels, and switch to the four-wheel drive state, which is simple to operate.
Extended data:
Four-wheel drive related information:
1. The adhesion of tires is closely related to the power transmitted to the road surface. With the increase of power, the cornering force of tire tends to decrease. The power is reduced, the steering force is increased, and the performance of wet road surface and lane change is improved.
2. For four-wheel drive vehicles, the engine power is transmitted to all four wheels equally, and the adhesion of all four wheels can be effectively utilized. Therefore, even if the accelerator pedal is suddenly stepped to the bottom, the wheels will not idle, thus improving the starting and acceleration performance of the vehicle.
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