Automatics are in vogue

25-09-2019

The question of whether to purchase an automatic or manual new car almost borders on philosophy. For many years, there was a popular belief that manual transmissions were for drivers who wanted to be fast and sporty on the road, while automatics were seen to be a "slowcoach" with higher fuel consumption. However, these stereotypes are no longer viable in view of the enormous technological advances that have been made. To that effect, the number of newly registered vehicles with automatic transmissions continues to rise in Germany. Whereas in 2000 only 20% of vehicles in Germany were equipped with automatic transmissions, today every second new vehicle registered is automatic – and the trend is rising, not least thanks to the increasing number of electric vehicles. But automatic is not the same as automatic! We will give you an overview and explain the advantages and disadvantages of the individual technologies.

 

Automated manual transmission

This transmission is designed like a manual transmission, but the clutch and shift processes are automated. In addition, a transmission actuator and a clutch actuator, which replaces the clutch pedal, are integrated into the system. Each gear change is monitored and controlled by electronics. The interruptions to the traction that result from this pose a serious disadvantage. They cause unpleasant and uncomfortable "jolting" and poor acceleration values, especially in vehicles with weaker engines. However, costs and additional consumption are limited.

 

Continuously variable transmission (CVT)

With this transmission type, the transmission ratio changes without a shifting procedure. Simply explained, in this transmission, two variable conical pulleys that run against each other are installed: they are connected by belts or a metal link belt. Depending on the gear speed, the transmission ratio of the pulleys changes and, therefore, so does the speed at the drive axle. This enables a smooth acceleration and an optimum engine speed adapted to the driving style. One disadvantage, however, is the background noise generated during high acceleration – the howl of the engine can be quite unpleasant to listen to. However, while mopeds have used a CVT (Continuously Variable Transmission) for a long time, they have only rarely been used in passenger cars.

 

Torque converter automatic

The best known automatic is the classic torque converter automatic. Here, a hydraulic torque converter (fluid clutch) operates between the engine and transmission, ensuring a high level of comfort when starting and shifting. A modern torque converter automatic is more acoustically pleasant as the RPM is kept relatively low and does not remain at a high level even during strong acceleration. One disadvantage compared to manual transmissions is that its consumption is usually slightly higher. It also requires a relatively large amount of space. This transmission type is very common in the USA (manual transmissions have always played a completely subordinate role there).

 

Dual-clutch transmission (also called direct shift transmission)

This transmission combines the advantages of manual and automatic transmissions. This is ensured by two manual transmissions, one for the even gears and one for the odd gears. One clutch is used per transmission part. It transfers the appropriate gear to the drive wheels. At each gear change, one clutch opens while the other closes. Since shifting takes place without interrupting the traction, the dual-clutch transmission achieves very good acceleration values that are not inferior to manual transmissions. It is also possible to switch to semi-manual shifting, for example using shift paddles on the steering wheel. The transmission does not require much space and the consumption values are just as low as with manual transmissions. Disadvantages include the mechanical clutch wear, high transmission weight and the surcharge, which is usually higher. This transmission type is now used by many vehicle manufacturers with different designations. For example, at Audi it is called S-tronic, at Mercedes-Benz they call it DCT and at Volkswagen it is DSG.

 

Image sources:

gettyimages #890205628 / loraks

gettyimages #178762749 / Bizhan33