Types of transmissions and how they work

Car names often come affixed with letters CVT, AGS, Prosmatic and others. For example, Civic RS Turbo LL CVT, Swift GLX CVT and Alto VXL AGS, etc. This is confusing for many as not every car owner is a car enthusiast as well. If you are one of those, this blog is for you. 

There are multiple types of transmissions used in different types of vehicles and these letters represent these transmissions. Let’s find a bit more about these but first, what is a transmission?

What is a transmission?

Simply put, a transmission is a mechanical part of a car that transmits and controls the power supply of the engine to the wheels. 

In the following lines, we’ll explore different types of transmissions, how they work, and the pros and cons of each.  

Types of Transmission

Let’s start with the most basic and common transmission. 

1. Manual transmission

A manual transmission is controlled by a manual clutch and gear stick. This clutch connects the rotational energy of the engine with the transmission’s input shaft. A fixed set of gears are engaged using a Synchro and gear selector fork ( the gear stick). The synchronization of the friction clutch and the gears ensure the smoothness of the ride. 

Manual transmission cars are now phasing out. New vehicles are using automatic transmissions, considering the ease of it. However, it does have its pros and cons. Let’s evaluate. 

Pros:

• The driver has complete control over the vehicle engine and transmission. Thus they can adjust the gear and power ratios variably. 
• These offer the utmost fuel efficiency.
• Manual transmissions have fewer moving parts, and hence there are fewer chances of transmission breaking down. These are also the ones with the easiest and cheaper repairs. 

Cons:

• It is hard to drive a car with manual transmission.

2. Automatic transmission

The term automatic transmission is self-explanatory. It means that the transmission operates automatically without any external interference. There is no need for a clutch and that’s why you don’t see any clutch paddle in the automatic transmissions. Conventional automatic transmissions use a torque converter to convert the energy from the engine and power the transmission. 

A car with automatic transmission offers the following drive options:  

• P – Parking
• R – Reverse
• N – Neutral
• D – Drive
• L – Low

Even for a new driver, it is very easy to drive a car with automatic transmission. It also helps them focus on the road better since it requires no gear shifting. Just put your car in the D mode and drive.

The letter “L” stands for low-gears. This locks the car in low gears for maximum torque. It also helps drivers to auto brake when descending a hill. 

Every piece of technology has its pros and cons. And so does this transmission. 

Pros:

• Easy to drive with minimal driver input
• Gentle learning curve for new drivers
• Drivers can focus on the road better

Cons:

• Fuel hungry transmission
• May jerk when gear shifts
• Fixed gear ratio means it’s not as responsive as manual transmission

3. Continuously Variable Transmission (CVT)

CVT stands for advanced Continuously Variable Transmission. The flaws in automatic transmission led to more modern CVT transmissions. CVT became a hot favorite for auto manufacturers in the early 2000s due to its excellent fuel average and performance. This new automatic technology was lightweight, efficient and durable due to fewer moving parts. 

CVT doesn’t have any specific gears; instead, the whole system works on a simple belt and pulleys. This system has infinite gear ratios that are pulled off depending upon the acceleration and power requirements. Endless gear ratios mean the fuel average is excellent since the car gears at higher rpm for a smooth ride.

Pros:

• Smooth and seamless riding experience
• Durable transmission
• Excellent fuel economy 

Cons:

• Constant nagging sound when you floor the car
• Slight delay in the acceleration 

4. Dual-Clutch Transmission (DCT)

A dual-clutch automatic is somewhere in between a fully automatic and a manual transmission. And this makes it the most complex transmission in cars. This is also the most premium transmission due to its many benefits.

Sports and luxury cars use this transmission over other transmissions due to its superior shifting and performance. As the name suggests, this transmission uses two clutches engaged with two separate sets of gears. One clutch is specific for the even gears, i.e., 2,4,6 and the other clutch is dedicated for odd gears i.e., 1,3 and 5. 

In DCT, one clutch is always ready to engage the gear making the shifting extremely efficient, seamless and quick. This performance transmission comes at a cost which you will find below in the cons. 

Pros:

• Seamless and quick shifting
• Cutting edge performance

Cons:

• Highly expensive to maintain and repair
• Complex components make it hard to repair

5. Auto Gear Shift (AGS)

Pak Suzuki launched AGS in 2017 in Cultus. This transmission had a mixed response from the drivers at first, primarily due to the lag in the gear shift. However, with time their opinions changed as they learned how to drive it. 

AGS is a manual transmission coupled with an automatic clutch acting as an actuator. Yes, only the clutch is automatic and not the whole transmission. It doesn’t have belts like CVT, torque converters like conventional automatic, or dual-clutch like DCT. Instead, the clutch actuator is attached to the ECU, automatically shifting the gear according to the throttle response. 

It’s not as seamless as CVT. To ensure smooth gear transition, the driver has to lift the foot off the pedal slightly. Once done, the ECU will direct the actuator to change the gear.

Credit: Suzuki Pakistan

Pros:

• Excellent fuel average
• Instant acceleration of a manual transmission
• Very responsive

Cons:

• Lag in gear change 

What to learn from this blog?

The Engine is indeed the heart of a car, but it’s the transmission that delivers the power to the wheels. With advancement, the transmissions also evolved. Today, we have transmissions that ensure durability, fuel average, convenience and performance.

In this blog you’ll find basic information on types of transmissions, how they work and their pros and cons. Let us know which transmission you prefer and why.