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Last Updated on March 30, 2020 by Team TRA

Every automobile has a number of complex parts that help in the efficient and long term functioning of the car. Some components such as automotive fluids and belts may seem trivial but are crucial to maintaining a healthy engine. Automobile parts are being manufactured all over the globe with precision and advanced technological methods. Some of the most important automobile components include the engine, gearbox parts, drive axle, steering and suspension, brakes, and so forth.

In this article, we’re going to take an in-depth look at the most important automobile components and parts, discuss their importance, as well as maintenance. We hope you can find some useful information here to apply for your own vehicle!

The 6 Most Important Automobile Components

Parts of an Engine

Each and every component of an automobile has significance. Modern-day vehicles have become a great deal more complex and have many more electronic parts than the muscle cars of the past. Although there are many complex parts included in modern automobiles, some of the parts are a mainstay — common and essential for every vehicle.

Some of the important components include:


One of the most important components of a vehicle includes the engine. This is the most important component of an automobile by all accords. The performance of a vehicle depends on its engine and it is the heart of every car.

Different types of fuels are used by engines including-

  • Diesel
  • Ethanol
  • Gasoline
  • Electricity

Engines require regular oil changes to stay lubricated and prevent wear and tear.

Gear Box (Transmission)

The Gear Box, or transmission, comes in at a close second to the engine and is what commonly needs attention when vehicles fail.

The transmission is what contains the different gears that the vehicle needs to shift into depending on speed. These gears transfer the engine’s power to the wheels of the vehicle. There are many types of gearbox parts in different cars.


Transmission is available in two types: the manual and the automatic models. As the speed of the vehicle varies, the gears can be switched from one ratio to another. The power of the engine is transferred to the wheels of the vehicle with the help of the gears.

Nowadays, most of the vehicles have automatic gears or transmissions. The gearbox is one of the most difficult parts of the vehicle to work on, and when restored can give new life to even the oldest of vehicles.


Care about safety? Another extremely important component of a vehicle is the brakes which help reduce and halt the speed of the vehicle. When the brakes are applied, hydraulic fluid is transmitted through the steel pipes to the wheels of the vehicles.

Obviously, the failure of this system may lead to some serious accidents. Though previously the entire system used to work upon human intervention, nowadays sensors are being installed in cars so that the car itself can sense the necessity of braking and take action. Whether you have a manual or sensor braking system, it is very important to maintain the brake parts such as brake pads, which can crack with age.

Drive Axle

Another important component includes the drive axle which helps propels the vehicle. Think of it as a large bar connecting the two wheels. The drive axle allows the vehicle’s operator to turn the wheels and control the vehicle. This is one of the largest auto parts in every car.

Oil Filters

Filters are essential in removing dust and abrasive particles from the engine oil. Such particles can harm the engine and prevent proper functioning. Oil filters are mainly used to segregate the engine oil from unwanted debris and dust particles. Most of the oil filters are classified as high-efficiency filters as it segregates abrasive materials from the engine oil.


The automotive chassis is the frame of the vehicle which supports the various parts such as engine, brakes, steering, axle, tires and so forth.

If the engine is the heart of the vehicle, the chassis is the skeleton. It is the most important structural part of the vehicle. Automotive chassis are usually made of light steel material or other sturdy materials like aluminum.

The chassis keeps the vehicle stiff and tensile. It ensures low vibration and noise in the entire vehicle. There are various types of chassis used in vehicles which include-

  • The backbone chassis
  • The ladder chassis
  • And the monochrome chassis

These days most of the vehicles use steel plated chassis as it ensures strength and durability.

Gearbox Parts and Oil Filters

Gearbox (Transmission) Diagram
Gearbox (Transmission) Diagram

There are quite a variety of gearbox parts included in the transmission. Most of these parts can be purchased from the online stores for replacement but that’s less than half the battle, you’ll need technical expertise to fix a transmission. Some of the parts include the gearbox cover, the shifter fork, the shifter rod, gearbox fork, and synchronizer rings or hubs.

Buying Parts from the Manufacturers

There are many manufacturers and suppliers who supply precision manufactured gearbox parts of different varieties. Parts from trusted manufacturers are highly resistant to corrosion, tensile, and of superior quality.

Most of the components produced by these manufacturers are guaranteed against thermal and chemical reactions. A new transmission also produces lesser noise, vibration, and is one of the most expensive components of the modern-day vehicle.

Finding the Right Oil Filters

In addition to gearbox parts, there are different types of oil filters available today. According to the specific design and type of filter material, some of these filters are classified as high-efficiency filters. It is a good idea to install a premium quality filter in your vehicle. It will help avoid clogging of the engine with dust and abrasive materials.

The efficiency of these filters is assessed by the number of particles collected in the filters as well as the rated mileage (how long it will last for).

Functions of Different Automobile Parts

Automobiles are common and can be seen in our daily life. With the development of the economy and the improvement of people’s quality of life, more and more people choose to buy cars (especially now in developing countries). Therefore, the automobile plays a more and more important role in our global society.

There is no doubt that automobiles consist of complex subsystems that work together to provide efficient and reliable transportation. Many different parts have different functions and performance. Some of them are quite familiar to us.

Up First: Pay Attention to the Engine

Among all the auto parts, the engine is the most important. Preventative maintenance will lead to steady and reliable engine performance. It can run on a wide variety of fuels such as gasoline, diesel fuel, and ethanol and so on.

Do you know how an engine works?

It takes air from the intake tract and fuel from the carburetor or fuel injectors and compresses these inside the cylinder. Then the spark plugs fire, igniting the air/fuel mixture, creating mini-explosions, and forcing the piston down in the cylinder, which turns the crankshaft. Ultimately that crankshaft combined with the transmission turns your wheels and sends you lickity-split on your way to your destination.

Drive Axle and Gear Box Interactions

In addition to the engine, the drive axle is also a necessary part. The drive axle is aptly named because it is a key component in making a car do what it does best: drive. It works in unison with the transmission to achieve results.

Generally, the drive axle takes the power from the transmission and channels it to the tires, which in turn propels the vehicle. Then, the transmission converts and moderates the power generated by the engine at the crankshaft and relays it to the drive axle. These parts work together to drive cars.

Automatic vs. Manual Transmissions

As you probably know, there are automatic and manual transmissions. The latter type is one in which the driver selects gears through the use of a shift lever and clutch pedal. While the former one can shift through forwarding gears by itself, and the driver only needs to select between drive (forward) and reverse.

Obviously, an automatic transmission is more convenient than a manual one, but they don’t last as long as some people do not think they are as fun to drive. Plus, performance enthusiasts argue that you give up control when you opt for an automatic. Cars with automatic transmissions are more popular among most drivers.

Alright, Stop: Brake Time

The parts mentioned above are mainly used to push the automobile forward.

However, what part do you need if you want to stop it?

The answer is the brake system.

The brakes use the power of hydraulic fluid to transfer the force the driver applies to the brake pedal to a clamping force that slows the vehicle’s wheels.

  1. The brake pedal is attached to a master cylinder. This pumps brake fluid through steel and rubber lines to each wheel.
  2. At each wheel, the caliper forces the brake pads to clamp down on the rotor. The rotor is a large steel disc that is attached to the wheel.
  3. Press that pedal down hard enough and boom, you come to a complete stop.

Regularly replacing your brake pads is a good idea. As you can imagine, they take a beating. Common issues with brakes can be due to cracked pads, air in your brake lines, or water damage.

Here’s a quick video to give you a visual aide:

Put It All Together: What Does it Take?

When compared to all other machines present in our society, an automobile is one of the only mass-produced machines that function when moving at high speed.

Taking into account the precision required to manufacture a well functioning engine that lasts over 100,000’s of miles and the knowledge to put together a body that is durable enough to protect the driver and riders…

Well, you can likely see why purchasing a new vehicle is so expensive.

Vehicle Appearance: Exterior and Interior
64 Mustang Car Exterior

Of course, the magic of the modern-day vehicle is hidden behind a (hopefully) comfortable interior and sharp looking exterior. The exterior of the automobile consists of panels like the hood, the doors, etc.

Exterior & Interior Materials

Some of the first cars used iron and panels of wood for their framework. But with the passage of time both the frames and panels were made of steel or other advanced materials such as fiberglass. And today aluminum is another popular choice such as seen in Tesla’s vehicles. A ton of effort is going into researching how to make electric cars as light as possible. This is done to extend their battery life and therefore mileage range.

The interior of vehicles has undergone massive changes with all the advancements in technology and electronics. Large touchscreens are commonplace, and luxury features such as steering wheel control, heated seats, automatic chair adjustment are just a few examples of the final touches manufacturers are adding to their vehicles.

Automobile Replacement Parts

The gradual development of the more complex vehicle had led to a great degree of technical knowledge being required to work on certain parts of modern-day cards.

Replacing and Repairing Automobile Components

There used to be a time when a man could repair his own vehicle with his own toolbox. Nowadays, dealerships have systems set in a place where car owners can bring their vehicles in for routine maintenance, tune-ups, oil changes, and repairs. Fortunately, devices such as OBD2 scanners allow the user to quickly diagnose what is wrong with a vehicle and hone in on the problem area.

auto part stores

For a long time, auto manufacturers were considered the only possible source of auto replacement parts. However, in the ’80s that scenario begin to change. Places like NAPA Auto Parts and Autozone started selling individual parts. Currently, you can even order many replacement parts and components online as long as your car isn’t too exotic.

The replacement parts market is nowadays growing rapidly in most countries following the trend of global vehicle ownership. People who own the most popular makes and models have a plethora of options available to them when ordering replacement parts or automotive fluids.

Use of Electronics: The Modern Age Vehicle

There have been huge developments in the field of science and technology in the past few decades. That trend doesn’t seem to be slowing down anytime soon. With the introduction of hybrid, full electric, and even hydrogen vehicles (and maybe even flying cars in the coming 10-15 years) our vehicles will continue to get more complex.

Like all other aspects of life, the processes in the automobile industry have been changed drastically through this development. In fact, modern cars and vehicles have evolved into intelligent and more sophisticated machines. In many ways, they think for themselves and the components truly understand the requirements of its passengers.

Automobile Electronics

Electronic Takeover

Nowadays, electronic systems are heavily used in most cars in order to make driving more comfortable and safer. Literally all the major systems in a car including the brake system, the fuel injection system, and the steering system are mostly controlled electronically. Soon enough, these systems will take over the task of driving. This will free up our hands and minds to do other things while we are in route to our destination.

The Necessity of Regular Servicing

Preventative maintenance is a big thing we push at Twelfth Round Auto. It is extremely valuable and most car owners overlook it. Done right, it can save you a lot of money over the long run. As far as performance goes, it will give you a better and smoother driving experience in the interim.

Engines can perform optimally if they are subjected to regular servicing and maintenance. The main advantage of servicing is that the cars are checked thoroughly and necessary repairs and replacements are made before something critical (and expensive) breaks down. Whether you choose to complete this maintenance yourself or have professionals do it, make it routine. This is a wise path to take as a car owner.

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