AMT Explained: How it Works and the Best Cars

Automated Manual Transmissions, more commonly known as AMTs, have become popular over the last decade. It's mainly because their cost-effectiveness has made the option of two-pedal driving accessible to a lot more buyers than before. The Maruti Suzuki Celerio was the first mass-market AMT car launched in India in 2014. At the time AMTs  were deemed rudimentary for wide scale adoption. 

Today, however, the story has changed and the cost effective AMTs offer a vastly improved driving experience, leading to their increasing popularity. If you own a car with an AMT gearbox or are looking to buy a new or used automatic car , this article covers the functioning of an AMT, its advantages and disadvantages, and the best AMT cars available in the market.
 

What is an AMT?

At its core, an Automated Manual Transmission is a manual transmission that operates like an automatic gearbox.  There are various types of automatic transmissions, but a car with an AMT has electronic or hydraulic actuators that operate the clutch and gear shifter to automatically change gears without human input. In short, an AMT simply combines the simplicity of a manual transmission with the convenience of an automatic transmission.
 

How does an AMT Work?

As an AMT is mostly like a manual transmission, which has an automated operation. The clutch pedal is absent in an AMT car and the clutch is instead controlled by an actuator (electronic or hydraulic). The traditional gear selector lever, like in manual cars, is replaced by a lever similar to the one found in automatic transmission cars. The various sensors detect engine rpm and throttle input and then signal the actuators to apply the clutch and change into the appropriate gear automatically, without human intervention. The actuators are controlled by a Transmission Control Unit (TCU), which is similar to an Engine Control Unit (ECU).

The TCU relies on different sensors in the vehicle to gather information. It then computes that information and makes a decision on when to use the actuators and shift a gear. They following sensors are found in most AMT transmissions:

1. Throttle Position Sensor - Measures the position of the throttle
    
2. Vehicle Speed Sensor - Uses wheel speed to calculate car speed
    
3. Engine Speed Sensor - More commonly known as RPM or revolutions per minute
    
4. Clutch Position Sensor - Detects the position of the clutch and helps in its actuation
    
5. Gear Position Sensor - Detects the current gear and helps in gear selection actuation
    
6. Pressure Sensors - Measure the pressure on the actuators

Complex AMT transmissions can use even more sensors, however, the ones listed above are crucial for AMTs to function and offer a comfortable driving experience.
 

Advantages of an AMT

AMTs offer many benefits, especially in Indian driving conditions, in offering a balance between price sensitivity and comfort:

1. AMTs are fuel efficient: Manual transmissions have historically been more fuel efficient than their automatic counterparts. However, advancements in technology have levelled the playing field, and with the precision offered by electronic control, some AMTs now boast a marginally better fuel efficiency figure than their manual counterparts.
    
2. AMTs are cost efficient: They are simple in their construction compared to other types of automatic transmissions, thus offering a cost advantage.

AMTs are cost effective as they are not only less expensive upfront, but also help in reducing running costs.
 

Disadvantages of an AMT

While they were once known for being problematic, the problems with AMTs have dialled down to quite an extent:

1. Jerky Shifts: AMTs were initially known for being jerky in their shift quality, and inducing a head nod in the passengers when changing gear. Modern AMTs have mostly dialled out this issue with Maruti Suzuki AMT transmissions being particularly smooth and the best in the business. Cars with AMTs launched after 2021 are particularly more refined than before.

1. Clutch Wear Issues: As AMTs use a clutch similar to a manual transmission car, it also can wear out similarly.

Over the years, AMTs have massively benefitted from advancement in tech. AMTs are an extremely cost effective solution, they are however, not as refined as other types of automatic transmissions.
 

Top Cars with an AMT in India

AMTs are only found on budget cars and and the best ones are found on cars made by Maruti Suzuki and Hyundai.

Is an AMT Right for you?

Choosing between different types of automatic transmissions can be confusing, but an AMT inherently has cost benefits. So, it's an ideal option for those who want the convenience of an automatic transmission for the least amount of money. 

If you seek a more refined experience, it is better to choose a vehicle with a torque convertor (AT) or DCT gearbox, however, they do cost a premium.

Conclusion

An AMT capitalises on the simplicity of a manual transmission while offering the convenience of an automatic. It is a great stepping stone for first time automatic transmission buyers as it works well in Indian conditions, and the learning curve from switching to an automatic from a manual won’t be as steep.