1. AWD
refers to a full-time four-wheel drive vehicle is traveling in the whole process has been maintained in the form of four-wheel drive, the engine output torque at a fixed ratio to the front and rear wheels is assigned, this drive mode can always have better off-road performance and handling, but not able to make adjustments torque distribution according to road conditions and high fuel consumption. Real-time four-wheel drive while the drive is switched with two four-wheel drive is controlled by a computer chip in the normal road, the vehicle travels in two-wheel drive mode, the road or off-road encounter wheel slippage, the computer will automatically detect and power distribution to the other two wheel. For real-time four-wheel drive mode, the control program will affect the merits of the intelligent drive form switching. In addition, there is a controlled manually by the driver to the switching drive and four-wheel drive in the form of (Part-Time 4WD). Now a lot of one or several SUV and off-road vehicles at the same time have more than four-wheel drive model to complement the short length.
shortcomings
It is detected by the slip of a tire, it began to deliver power to the tires do not slip, so that the reaction will be slower. It is important that these adhesive or electronic differential, is not quite as mechanical differential lock as the lock power 50:50. For this reason, full-time four-wheel drive was only die-hard off-road despised by those who think they are just fake off-road, four-wheel drive and not as climbing wading.
Advantages
In theory it is the best way to drive the vehicle, which enables the wheel grip more firmly and more comfortable turning at high speed, is more easily manipulated , which can increase the performance and safety performance sports car. Because the four wheels at any given time power distribution, when a wheel slippage occurs, the system will automatically intervene to redistribute power four wheels, four wheels to ensure that at all times the highest affixed to sex, this class system has a very distinct advantage in handling on slippery roads. Therefore, more and more cars use four-wheel drive SUV and its effect on not only full-timeOff-road, four-wheel drive stability control and active safety is to bring them to another object, especially some high-performance cars.
all-wheel drive vehicle will be more excellent than 2WD (FWD points and RWD) and security. In theory, AWD 2WD more than more than doubled traction, driving the car is based on its continued smooth traction, stability and traction is mainly determined by the method of driving the car, the engine power output will be assigned to four by the transmission system tires allocated to the two tires compared, the result is AWD can easily travel in 2WD not safe driving in traffic, the car has agile handling, to achieve security and stability, that is, no matter what the weather and how to travel kinds of pavement (on wetlands, rugged mountain road, detours); the driver can easily control every movement, thus ensuring the safety of the driver and passengers. It is because of the presence of AWD, in order to provide a car ldquo; active safety, active driving rdquo; opportunities.