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[YesAuto Four-wheel-drive Detailed Explanation] Hello everyone, in this issue of “Fun Four-wheel Drive”, we will analyze the Buick brand's four-wheel drive technology. There are currently three Buick SUV models on sale in China, namely Angkola, Ankewei, Ankeley. Since Angkola’s four-wheel drive structure is exactly the same as its compatriot brother Chevrolet Chuangku, we will not repeat it, you can refer to this article to understand the specific content: “Introduction to the Chevrolet brand four-wheel drive system”. In addition, considering that Encore, which has been on the market for many years, is approaching the end of its product career and will be replaced in the near future, we decided to wait for it to complete the replacement before testing its four-wheel drive system for everyone. Therefore, in this article, we have only one protagonist, and that is the popular niche in the joint venture SUV market this year: Ankewei.

Encore is the second joint venture SUV launched by Buick in China. It is positioned as a medium-sized SUV with two different power systems. The 20T model uses a 1.5T engine with a 7-speed dry dual-clutch gearbox, and the 28T model is matched It is a combination of 2.0T engine and 6-speed automatic manual transmission. Envision adopts a set of timely four-wheel drive system, and also provides two different versions for consumers to choose. The official name of the two four-wheel drive is the smart four-wheel drive and the all-road smart four-wheel drive. The difference between the two is mainly in the left and right rear. Wheel power distribution. Elite and luxury models are equipped with intelligent four-wheel drive, while the four-wheel drive of the all-around flagship and the all-around sports flagship is slightly more advanced, so let's take a look at the difference between the two.

Elite and luxury four-wheel drive test

Let's take a look at the performance of the “smart four-wheel drive” used on the elite and luxury models. The one who participated in the test was the Angkewei 20T four-wheel drive luxury model. This timely four-wheel drive system also has its own unique structure. The multi-disc clutch located on the side of the rear differential is responsible for transmitting power to the rear axle. Its driving mode is front-wheel drive when driving on the road. When the system detects wheel slip, Part of the power is transmitted to the rear wheels by pressing the clutch plate to achieve the purpose of distributing the front and rear power.

● Front and rear axle power distribution test

The relatively elementary test of power distribution between axles is not difficult to Envision. The combination of the four-wheel drive system is fast and in line with the same level. Envision successfully passed this test.

  Cross axis test

The cross-shaft test is slightly more difficult. On the basis of connecting the rear axle transmission, the limited slip between the front and rear wheels requires intervention to complete this test. During the test, the electronic limited slip intervention is timely and the braking force is sufficient. Ankewei passed the test.

● Single wheel landing mode

In the simulation test where all three wheels lost their grip, the low-equipped four-wheel drive Angkewei was slightly weaker. Although the idling wheels have a certain braking effect, the power is transmitted to the wheel on the side with adhesion. Insufficient, ultimately unable to escape.

● Test video

●Flagship and sports flagship four-wheel drive test

Buick manufacturers define the four-wheel drive of the flagship and sports flagship models as “all road conditions intelligent four-wheel drive”. The main difference from the intelligent four-wheel drive system is that it has two multi-disc clutch-type limited slip on the rear axle. Speed gear, the power from the front axle can be transmitted through two limited-slip differentials and distributed to the left and right rear wheels as needed. Let’s take a look at its structure and specific performance.

Compared with the smart four-wheel drive system on the elite and luxury models, the rear axle is equipped with two sets of multi-disc clutch-type limited slip differentials. The computer controls the two multi-disc clutches on the rear axle to control the front and rear wheels and the left and right wheels. The power distribution between the rear wheels is actively controlled. According to the official statement, this four-wheel drive system can theoretically achieve a continuous distribution between the front/rear wheels 50:50 and the rear left/right 0:100-100:0.

● Front and rear axle power distribution test

Cross axis test

    The first two tests are completely indistinguishable from the previous 20T luxury model, and Envision can easily get out of trouble. Let's focus on its performance in the test of three sets of open pulleys.    

● Single wheel landing mode

Judging from the actual test process, the two sets of four-wheel drive are basically the same when facing a single wheel with adhesion. It can be seen that the 28T model equipped with a 2.0T engine is significantly more powerful, and the wheel idling is also greater. , But the active power distribution effect of the rear axle is still not obvious, and the electronic limited-slip effect is basically the same as the 20T model, and ultimately failed the test.

● Test video

● Summary

The four-wheel drive performance of Ankewei is fully capable of urban road conditions, which is also related to its market positioning. After testing, we can draw the following conclusions for this four-wheel drive system: the low-end four-wheel drive system matched by Ankewei The drive system belongs to the mainstream level of the same level. Although the four-wheel drive system on the high-end models is more gimmick, the final test result is “random. For this type of SUV, it’s not good at spending time in the wilderness. When buying it, it’s okay to follow the principle of good enough. (Picture / text car home to find Zhuo)