"Full-time four-wheel drive, please don't delay", what is it?

Why not tow a full-time four-wheel drive?

Maybe sometimes when we wander around the roadside, we will see all kinds of stickers on some car bodies, some of which are funny car stickers such as "I am shy, don't kiss me", and some are car stickers reminding signs such as internship signs. These slogans can be understood by us at a glance, but some people may not understand them. For example, some cars posted "full-time four-wheel drive, no towing", and some people simply don't know what full-time four-wheel drive is, let alone why. Let's explain.

There are many ways to drive a car, including front-wheel drive, rear-wheel drive, time-sharing drive and full-time drive.

The so-called front wheel means that the front wheel is the driving wheel, the power is mainly output from the front wheel, and the rear wheel is the driven wheel, so there is no power output. Similarly, I don't think it is necessary to explain the rear drive. Time sharing and full-time driving are more advanced. All wheels of full-time four-wheel drive are independent, and there is a central differential to adjust the speed difference.

Part-time four-wheel drive can be two-wheel drive or four-wheel drive.

The two-wheel drive is equivalent to ordinary vehicles, and the owner can adjust the two-wheel drive and four-wheel drive according to the road conditions at that time. When the road conditions are good, two-wheel drive is often used, and when the road conditions are bad, four-wheel drive is often used to improve the power to deal with potholes. Multi-disc clutch and additional adhesive clutch are two main basic types of full-time four-wheel drive.

There are two main reasons why cars are towed away:

One is that the car broke down on the road and could not move, and the other is that it was forcibly towed away by the traffic police in violation of traffic laws. The way of the latter trailer is that the front wheel lifts the rear wheel and lands, which is the biggest nemesis of full-time four-wheel drive. In this trailer mode, the rear wheel rotates on the road due to friction, but the front wheel cannot rotate because it is overhead. As we all know, the central differential connects the front and rear axles, and the rotation of the four wheels is controlled by it. They are all driving wheels, and this situation that only the rear wheel rotates and the front wheel does not move can easily lead to the damage of the central differential.

It's okay to mop the floor for a short time and not far away, but if it's a long-distance trailer, the damage to the car is still quite great. In this case, all four wheels should leave the ground and the wheels should not rotate. If it is a part-time four-wheel drive, it can be used as an ordinary vehicle traction as long as it is switched to two-wheel drive.