What is a Transmission?

An automobile is composed of multiple parts, which all work together so your vehicle can run as beautifully as it does. One of the most important components is the transmission system, which powers the wheels, allowing them to move forward and backward. Without this system, your vehicle wouldn’t be able to move at all. Here, we will go into more detail about what exactly a transmission is, and what it does every time you hit the accelerator.

How A Car Transmission Works

Your cars transmission is a complex system that helps your car's engine to deliver power to the wheels. The transmission is made up of many different parts, including the gears, clutch, driveshaft, and differential.

The transmission is responsible for transferring the power from the engine to the wheels. The transmission uses gears to change the speed of the car. The higher the gear, the faster the car will go. The lower the gear, the slower the car will go.

To fully understand your car’s transmission system, you first need to understand how the car’s engine operates. This YouTube video shows the inner workings of a transmission and visually explains how your engine powers your car.

Here's how it works:

1. The engine has a combustion chamber, in which fuel is ignited.
2. A mini-explosion takes place that expands heat and gas, pushing the pistons in the engine’s cylinders into motion.
3. As the expansion pushes the pistons, they start spinning, moving up and down the engine’s crankshaft.
4. In turn, the crankshaft turns the drive wheels, and the energy from the explosion is converted into mechanical energy.

So, where does the transmission system come into play during this process? Without the transmission, the power generated from the explosion in the combustion engine would be too high. The excessive power would prevent you from starting or stopping your car, or driving it at slow speeds. Most transmission systems have five to six gear sets and some gear strains that allow you to control the power being delivered to the vehicle without altering the engine’s speed.

Transmission systems are critical components in every vehicle, as they ensure that your vehicle runs at the correct speed without being too slow or fast for your requirements. They also ensure that the correct amount of power is being supplied to your wheels. Without a transmission, your car would be unreliable and unsafe to drive because you would not have control over starting and stopping.

What Does the Transmission System Do?

By now, you probably understand that without a transmission system, your vehicle’s engine would destroy itself. The engine would turn too quickly and lose its structural stability. Over time, it would overheat or shake itself to pieces. The transmission prevents this from happening by harnessing the speed and limiting the velocity.

The transmission is responsible for changing gears, depending on your accelerator input and car’s speed. Its main objective is to keep the engine’s RPM appropriately low. There are two benefits of keeping your transmission system well-maintained and taking it for tune-ups every 30,000 miles:

1. Decreased fuel consumption
2. No overload on the engine when turning gears

The transmission system also lets you control the engine’s energy whenever necessary. When you need to drive slowly, you can stay in a low gear to avoid damaging the engine. When you want to drive at a higher speed, you can shift to a higher gear to optimize your vehicle’s power by turning the wheels quickly.

Types of Transmission Systems

There are three different types of transmission systems: Manual, Automatic & CVT's.

1Manual Transmission

This type of transmission system has a shifter and a clutch pedal that the driver uses to manually shift gears. There is a set of gears and a pair of output and input shafts. The driver manually selects the proper gear using the clutch, pressure plate, and flywheel after engaging or disengaging the clutch. The clutch is crammed between a pressure plate and flywheel, and the driver must push it before shifting gears. Different types of manual transmission systems include:

• Dual-Clutch
• Unsynchronized
• Synchronized/Constant Mesh
• Automated
• Single-Clutch
• Preselector

Learn about manual transmission repair here.

2Automatic Transmission

With automatic transmission systems, the process of powering the transmission takes place inside the transmission itself. It does not use a clutch to shift gears, but instead relies on torque converters. Below are more details about automatic transmission systems:

• Direct-shift gearboxes have two clutches that disengage alternately while changing gears, thereby ensuring fast shifts and smooth acceleration.
• The Tiptronic gearbox allows manual shifting via the shifter. However, a manual transmission is not allowed after set limits.
• Hydraulic is the fluid inside the automatic transmission system.
• Electric vehicles use single-gear systems for power transfer to the wheels.

Learn about automatic transmission repair here.

3CVT Transmission

Continuously Variable Transmission (CVT) is a pulley-based system that is common in small vehicles, such as ATVs, snow mobiles, and some hybrid vehicles. It contains a small drive setup with a secondary driven clutch, connected with a chain or belt.

No matter what type of transmission system you have in your vehicle, the gearbox will work almost exactly the same. The only difference is whether the driver manually pushes the clutch to change gears, or if the gears shift automatically.

The transmission is an integral yet complex part of your vehicle, so you need maintain it in order to keep your car in good working order for the long haul. However, you can’t trust just any mechanic to take care of this important system. Speedy’s Transmission Shop in Richmond, Virginia, provides the trusted transmission expertise you need, with unmatched diagnostic, repair, tune-up, rebuild, and upgrade services.

Learn about CVT transmission repair here.