What Is a Transmission In a Car?

A car’s engine can’t propel it without a way to get the power to the wheels. And to do so, it needs to be under control or the engine would stall when you stopped. The system used is known as a transmission since it transmits power to the wheels.

It’s a major component in your vehicle, and a new transmission can easily range from $1,500 to $3,000 or more.

What is it, and how does the transmission work? Here’s what you need to know.

What Does the Transmission Do?

The transmission is one of the most important parts of your car. It is responsible for transferring power from the engine to the wheels. Without a transmission, your car would not be able to move. There are two main types of transmissions, manual and automatic, and a few variations of auto transmissions. Manual transmissions typically have five or six forward gears that the driver must shift between using a lever, as well as a reverse gear. Automatic transmissions have a torque converter that helps to seamlessly change gears without the driver having to do anything. For vehicles, there are commonly four or five gears in an automatic transmission, although some newer models have ten or more.

Both types of transmission have their own benefits and drawbacks, so it is important to do your research before choosing which one is right for you. Whether you are looking for a transmission for a new car or need to replace the transmission in your current car, understanding what transmission does and how it works is essential.

How Does a Transmission Work?

The engine produces power in the form of rotational energy. The transmission takes this rotational energy and converts it into linear motion, which is then transferred to the wheels. In order to do this, the transmission must be able to change gears. Depending on the speed of the vehicle and the load being carried, different gears will be used. 

The gears in the transmission are what allow it to change gears. They are located in what is called the gearbox. The gearbox contains a number of different gear ratios. Each ratio corresponds to a different speed and load combination. When the transmission needs to change gears, it does so by selecting the appropriate gear ratio. 

The actual process of changing gears is done by a device called a clutch. The clutch is what allows the transmission to disengage from the engine. This is necessary because, in order for the transmission to change gears, the engine must first be disengaged. The clutch accomplishes this by using friction to hold the engine in place while the transmission changes gears. In the case of an automatic transmission, a torque converter disconnects the engine’s rotation from the gears.

Once the new gear ratio has been selected, the clutch is released and power is once again transferred to the engine. The entire process happens very quickly and smoothly, and you usually don’t even notice it happening – unless you’re operating a manual transmission or shifting an auto transmission on your own.

Types of Transmissions

Generally, there are automatic and manual transmissions. Automatic transmissions also have a couple of options that are becoming much more popular including CVT transmissions, or continuously variable transmissions, and DCT transmissions, or dual clutch transmissions. Here are the differences.

Manual Transmission

What are transmissions that you need to move the gearshift lever yourself for every gear? Some call them standard transmissions or stick shifts, but they’re most often called a manual transmission. It’s a type of transmission that is operated by the driver, rather than by an automated system. In a car with a manual transmission, the driver is responsible for shifting gears in order to change the car’s speed. 

To do this, the driver must first depress the clutch pedal, which disengages the engine from the transmission. The driver then uses the gear shift to select the desired gear. Finally, the driver releases the clutch pedal, Which allows the engine and transmission to reconnect and engage. This process must be repeated every time the driver wants to change gears. 

While it may seem like more work than an automated transmission, a manual transmission offers drivers greater control over their car’s speed and performance. As a result, manual transmissions are still popular among driving enthusiasts.

Automatic Transmission

An automatic transmission is a type of gearbox that uses a fluid coupling instead of a manual clutch. This means that the driver doesn’t have to operate the clutch pedal every time they want to change gear. 

The transmission is controlled by a computer, which selects the correct gear based on input from sensors around the vehicle. This system usually includes an overdrive gear, which helps to improve fuel efficiency by reducing engine drag at high speeds. 

Automatic transmissions are often seen as being easier and more comfortable to use than manual transmissions, but they can be more expensive to maintain and repair.

Continuously Variable Transmission

A CVT transmission is a type of automatic transmission that uses a pulley and belt or chain system to change gears. The transmission is made up of two pulleys, the drive pulley and the driven pulley, connected by a belt. The drive pulley is connected to the power input, while the driven pulley is connected to the wheels. 

To change gears, the transmission adjusts the size of the pulleys to create different gear ratios. This allows the engine to run at a constant speed, regardless of what gear the car is in. As a result, CVT transmissions can provide smoother acceleration and better fuel economy than traditional automatic transmissions. 

While CVT transmissions are typically found in smaller vehicles, they are also becoming increasingly common in larger cars and trucks.

Dual Clutch Transmission

Another less common type of automatic transmission is called a dual clutch transmission, or DCT. In a DCT, there are actually two separate clutches that control even and odd gears. The advantage of this type of transmission is that it can shift gears very quickly and smoothly. Even if you’re accelerating hard, you’ll barely feel the gear changes. 

Another advantage is that since there are two independent clutches, one can be engaged while the other is disengaging. This allows for very fast and smooth gear changes with no interruption in power delivery.

 Dual clutch transmissions are often found in high-performance cars, but they’re also becoming more common in regular passenger vehicles as well.

What Transmission is Best?

The transmission option that’s best comes down to a personal preference as well as what’s available. 

  • Manual transmissions are popular for driving enthusiasts and sports car owners. 
  • Automatic transmissions are a common choice for uncomplicated driving. 
  • CVT transmissions are excellent for fuel efficiency and smooth acceleration. 
  • DCT transmissions are popular for high-performance models and those who drive them. 

Shop for the car you want, then get to know the transmission it has. And it’s a great idea to learn how to drive the different types, especially manual transmissions, as a life skill. 

FAQ/People Also Ask

Is it worth it to fix transmission?

In most cases, repairing a transmission issue is a good investment since the car’s value is severely depreciated if it doesn’t drive.

How much does a car transmission cost?

The cost of a transmission ranges significantly depending on the vehicle. You can find replacements from $1,000 to more than $5,000, and you’ll need to narrow the choice down for your exact vehicle build.

How do you know if you have a transmission problem?

Usually, a Check Engine light will come on for a transmission issue. As well, you might feel the car clunk when it’s shifting, make noises when you’re accelerating, or it might not move at all.

Is it better to replace a transmission or get a new car?

Before you replace your car, it’s a good idea to replace a blown transmission. Unless it’s an older model, you’ll often get the value back for the replacement.

How much will it cost to fix my transmission?

It varies. A repair can be as little as a few hundred dollars or more than a few thousand. An accurate diagnosis by a technician is always advised.

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