There was a time in India when automatic transmissions were considered to be an aristocratic fitment, something which is not accessible for the average car buyer. However, with the advancement of technology, automatic transmissions have become more affordable than ever and now several cars below Rs. 5 lakh bracket come equipped with one. The ever-worsening traffic conditions have further helped in increasing the popularity of automatics as it makes a car quite hassle-free to drive even in heavy traffic conditions. However, there are basically four different types of automatic transmissions available in the market which can create a little bit of confusion when buying a car. To save you from the trouble, here are the four different types of automatic transmissions classified according to their USPs. Read along to find out which one suits your needs the best.
Automated Manual Transmission (AMT)
For: Affordability and fuel efficiency
AMT or Automated Manual Transmission is the cheapest automatic transmission option available in the market. It is mostly offered in hatchbacks and sub-4 meter sedans/SUVs. In India, the sales of AMT type automatic transmission is probably the highest among other automatic options due to its affordability. The way an AMT transmission works is quite as simple as a manual transmission. An interesting fact about them is that the AMT technology in its current form was actually derived from the modern F1 cars. In AMT, the clutch and gear shift action are automated making it different from a standard manual gearbox. It is also referred to as the semi-automatic gearbox many times.
However, AMTs have a downside too. They can get quite Jerky at higher RPMs, which may soil the driving experience a bit. AMT is offered in affordable cars like – Tata Nano, Maruti Alto, Renault Duster and some expensive cars like Fiat Abarth 595 and even a few older Ferraris. Their good fuel efficiency and low cost is what makes them so popular. It is an ideal choice for people who want the convenience of an automatic gearbox but also don’t want to compromise on fuel efficiency along with affordability.
Continous Variable Transmissions (CVT)
For: Refinement and smoothness
Next comes the CVT gearbox which is quite different from AMT. The AMT system uses a servo to operate clutch but the CVT does not have any gears itself! Actually, the CVT transmission system employs a couple of discs that convey torque linearly across the RPM range. This type of gearbox is the most common choice for the scooters sold in the Indian market. The advantage of having a CVT gearbox is that it offers a very smooth driving experience with minimum noise levels. In India, various cars like the Nissan Micra, Maruti Baleno, Honda City, Honda Jazz come equipped with CVT transmission. Honda also offers paddle shifters on the City and the Jazz CVT models. Therefore, if you want a very smooth automatic gearbox with low NVH levels, CVT is the choice for you.
Dual Clutch Transmissions (DCT)
For: better Performance and quicker shift times
DCT (Dual Clutch Transmissions) or DSG as they are referred to as some times are among the most advanced automatic gearboxes, leaving aside the sports/supercar category. The biggest advantage of having a DCT gearbox is the lightning-quick shift times it provides. A DSG transmission uses a dual clutch system which makes them highly responsive and fast. It uses the second clutch which works out the gear you’re likely to need next and gets it ready. This translates into better shift times. DCTs come in wet or dry configuration, depending upon the torque rating of the paired engine. It is usually found in high-end luxury and performance cars. Indian cars with DCT/DSG gearboxes consist of the Volkswagen Polo GT TSI, Skoda Rapid, Ford Figo and many more. DSG should be your pick if you enjoy the thrill and driving pleasure of a powerful engine-automatic gearbox combination. The fuel efficiency, though, takes a bit of a hit with DCTs.
For: Want an automatic box but no other choice available
Last on the list and among the oldest automatic gearbox systems, the torque converter units have been around for long. They are quite old and hence the mechanism behind their operation is quite complex. They use a planetary design gear system with turbine and impeller. The impeller is filled with a fluid which is pushed by centrifugal force in order to turn the turbine. This mechanism results in a lot of transmission loss which results in poor fuel efficiency. Torque converters are slowly being phased out more advanced options. Some examples of torque converter gearboxes in cars consist of the Mahindra XUV500 and Tata Hexa.