CVT, AT, dual-clutch automatic transmission, which is more reliable? After reading you will know how to choose

26/05/2021

I remember once in the 4S store to see a car, a customer may not usually look at the reason for the car, in the store frantically asked sales of various questions about the car, after listening to the sales of a variety of transmission pros and cons is entangled to autism.

So is the transmission really that difficult to choose?

The transmission as the most important part of the car transmission is related to the car power output, a good transmission can be smooth and efficient distribution of engine power to the wheels. Now the transmission on the market is roughly divided into 5 types, so choose a suitable transmission for yourself has become a particularly critical point when buying a car, let's take a look at the advantages and disadvantages of these transmissions.

1、MT transmission

MT transmission is often referred to as manual transmission, its principle is to change the position of the gear bite in the gearbox by hand paddle, in order to change the transmission ratio to complete the shift, the entire shift logic completely follow the driver.

The advantage of the manual transmission is that it is extremely fun to drive, the entire structure of the transmission is simple, low manufacturing costs, easy maintenance, and very fuel-efficient. But the disadvantage is also obvious, is that shifting is extremely tedious, each shift requires the hands and feet to work at the same time, and for people who are not familiar with the temperament of the automatic transmission is easy to stall.

Now there are not too many manual gearbox cars on the market, but I still believe that the driving pleasure of manual gearbox cars is not given by automatic gearbox cars.

CVT、AT、双离合自动变速箱,哪个更可靠?看完你就知道怎么选了 (图1)

2, CVT transmission

CVT transmission is a continuously variable transmission, this kind of transmission does not have specific gears, some models will let the computer simulate the gears for the sake of the driver, but in fact, there is still no shift step. The reason for this is that its ability to withstand is much more fragile compared to other transmissions, the belt's limited ability to withstand makes it impossible to use in high horsepower cars, and CVT transmission compared to other transmissions, its normal driving and acceleration capabilities are not too aggressive, very smooth, so this transmission is only suitable for pure grocery car, and this transmission is really not suitable for intense driving.

CVT、AT、双离合自动变速箱,哪个更可靠?看完你就知道怎么选了 (图2)

3、AMT transmission

AMT transmission is known as electro-mechanical automatic transmission, this is a traditional MT transmission with a set of electronically controlled hydraulic operating system to achieve automated gear shifting, is like a person under your hood, when your engine speed reaches a certain level to help you step on the clutch shift. The advantage of this kind of transmission is that the cost is very low, the disadvantage is that the ride comfort is not good, the stutter is too serious, there is no smoothness, and the shift process is very easy to produce power interruption.

CVT、AT、双离合自动变速箱,哪个更可靠?看完你就知道怎么选了 (图3)

4、AT Transmission

AT transmission is known as hydraulic automatic transmission, also known as manual transmission, is now one of the most widely used transmission, in a variety of price models have been applied to.

As the name implies, it can switch freely between manual and automatic gears, taking into account the driving pleasure of manual gears and the convenience of automatic gears, as well as saving the trouble of stepping on the clutch, and if the model has shift paddles, it can also be shifted through the shift paddles.

The AT transmission consists of a torque converter, planetary gear, shift actuator, shift control system and shift manipulator. The principle is to shift the gears hydraulically, automatically shifting according to the depth of the accelerator pedal and the speed of the car. the AT transmission now has up to 10 gears, and the increase in gears brings faster shifts, smooth power output and better fuel economy.

The advantages of the AT transmission are comfortable driving, easy operation and low failure rate. The disadvantage is that it takes up a lot of space and has a complex structure that brings high maintenance costs. There may also be problems such as confusing shift logic due to the trip computer and other factors.

CVT、AT、双离合自动变速箱,哪个更可靠?看完你就知道怎么选了 (图4)

5、DCT transmission

DCT transmission is another more common transmission, known as dual clutch transmission. This type of transmission uses two sets of clutches, one clutch is used to control odd-numbered gears and the other clutch is used to control even-numbered gears. One clutch is working and the other clutch is ready to work. The advantage of this is that it solves the power interruption problem of AMT gearboxes and solves the shift stutter perfectly. Since two clutches are working, the shifts are extremely fast. Since the shifts are more direct, there is less power loss and better fuel economy. Generally dual clutch transmissions are divided into dry dual clutch and wet dual clutch. The transmission efficiency and shift speed of dry dual clutch is faster than wet dual clutch. The disadvantage is that the heat dissipation is poor and the failure rate is higher than that of wet dual clutch. The wet dual clutch is immersed in the transmission oil, so the heat dissipation is better and the failure rate is lower than the dry dual clutch. The disadvantage is that the maintenance cost is higher, and the shift speed is not as fast as the dry dual clutch.

CVT、AT、双离合自动变速箱,哪个更可靠?看完你就知道怎么选了 (图5)

So how can the advantages and disadvantages of these two dual clutch transmissions be perfectly resolved? The PDK transmission is the only mass-produced dual-clutch transmission for rear-wheel drive models. The cheapest model with a PDK transmission lands at over $700,000.

The PDK transmission is extremely heat dissipating, with dual coolant fluid partitioning and special cooling line design, one to provide oil to the hydraulic system and one to lubricate the gear set, ensuring good heat dissipation under different operating conditions, and multiple ejection starts without causing overheating. The PDK transmission's control unit also fine-tunes itself based on feedback from each sensor to provide the driver with the best and most efficient shift pattern. The cost of PDK transmission is also extremely high, disassembled parts are to be sold to tens of thousands of dollars, maintenance costs are also very high, but this still can not stop people's love for PDK transmission, from ordinary car owners to performance players to professional drivers are all praise for PDK transmission.

CVT、AT、双离合自动变速箱,哪个更可靠?看完你就知道怎么选了 (图6)

This is all the transmissions that can be seen on the market now, but each transmission has their better brands, for example, ZF's automatic transmission is mainly used in the entire BMW series, and is also one of the best reputation AT transmission. There is also the Aisin transmission made in Japan, which is used in almost all Toyota models, including many domestic models such as the Link 03+ and Link 05, which use the Aisin transmission. Those who like manual gearboxes for driving pleasure can choose the Honda Civic two-box models that have just been launched. Dual clutch gearboxes are also widely used in Mercedes-Benz.

Since the transmission plays a vital role in the car, it is important to choose a good transmission to suit your needs for the car, because each transmission has its own advantages and disadvantages, so you have to understand which aspect you value more.