Common Brake System Components and Short Descriptions

All cars have several systems. They are mandatory, and they will be present as long as cars exist. One of them is your brake system. Brake system components may vary depending on the make and model, but generally, they work in the same principle. Today we will help you understand all about the components and why they are important. Your brake system must be in perfect condition 24/7/365.

What is a brake system?

A brake system is used to stop the wheels of the car and therefore stop the vehicle. All systems use hydraulic fluid to operate, and you may need to know how to bleed brakes by yourself in order to get the best performance. Brake system components won’t work properly if there is air trapped inside the system.

A brake system is complicated, and it has a lot of components. On the other side, we can see that it works in a very simple principle. When you press the brake pedal, the oil will reach the calipers on all 4 wheels and apply pressure to the caliper pistons. They push the pads against the rotors or discs and cause friction. This also means that the wheels will slow down their rotation and therefore slow down a car. The performance is measured in stopping distance, and we can see that hypercars can stop from 60 mph in 20-30 feet. Ordinary cars have less powerful brakes, so they will need a longer distance to stop.

Types of the braking system include rotors with calipers and drums. The first system has been implemented into cars since the 60s, and it is still the most efficient method. Drums are usually obsolete, and we can see them on older cars or on the rear wheels of more affordable new cars. They are less efficient than the rotor systems, and they are not as safe as you would expect. Each one of these systems is known as a hydraulic braking system. It means that it uses hydraulic fluid to stop the car. These are the only types of brake systems available on all cars.

The chances are high that your car has rotors with calipers. You can see them through the spokes of the wheel, and you should invest a serious amount of time into making sure the system is working properly. One, an important part of maintenance, is to know how to bleed drum brakes or rotor systems. The process is the same.

brake system diagram

Brake system components and Short Descriptions

Now you know what a brake system is and how it works, but you still need to know something about the main components found in these systems. Below are all the parts that are already in your car, and you can check their state at any given moment. This is the most complete brake system parts list you can find these days.

Brake pad

brake pads replacementBrake pads are used for systems that have rotors. Each caliper will have two pads, and they will cause friction by literally catching the rotor. When this happens, the car will slow down. Brake pads are made from a mixture of materials, including brass and many others. The goal is to cause as much friction as possible when the brake is applied. This part should be replaced as soon as you head the sound while braking or after a specific mileage that will be provided by the brake pad manufacturer or car manufacturer. Usually, pads that are softer and provide better braking have to be replaced after shorter mileage. Old brake pads can significantly decrease the function of a brake system.

Brake shoesbrake shoes replacement

Brake shoes have the same role as brake pads, but they work in a completely opposite way. They are located inside a drum, which is located on the axle. When you apply the brake, shows will expand and cause friction with the drums. This causes your car to slow down. They have a slave cylinder that has Brake Bleeder on it and used to remove trapped air. Keep in mind that this is an obsolete system, and you won’t find it in new cars. It was common a few decades ago, and today only small, cheap cars have it.

Brake rotor/ Disc

disc brake componentsHere we can see one of the main components of disc brakes. The name is derived from this part. These are massive rotors you can see through the wheel, and they spin with the car. Once the brake pedal is applied, the brake pads will press the rotor and cause it to stop. This system is upgraded compared to drums, and it can be seen in all modern cars. It is also mandatory for sports cars and can upgrade your car’s needs. These brake system components usually have holes that are designed to help the rotors cool down and remove rocks and dirt. The two main types are standard and ventilated rotors.

Brake drum

brake drum percussionBrake drums are used alongside brake shoes. If you recall, we did mention that brake shoes will expand and cause friction with the brake drums. The name is redelivered simply due to the fact this component looks like a drum. Eventually, you will have to replace the drums. The constant friction causes them to lose material and decrease the stopping power. One of the additional drawbacks of this system is the lack of paint on the drums. They will rust over time, which doesn’t decrease their strength but has a negative impact on the look.

Brake caliperbrake caliper replacement

A brake caliper is used alongside brake rotors. It doesn’t move, but it will contain brake pads that move. This is the component you can see on most cars. It is massive or reasonably large, and the size depends on the size of the rotor. Larger rotors require larger calipers and brake pads. An important thing to add is that brake calipers can be easily removed and repainted when needed. They contain pistons that use oil to push the brake pads. More pistons, stronger pressure, and better-stopping power. Brake Caliper Grease is used to lubricate the surface where brake pads and pistons maker contact.

Read Also: Brake Caliper Sticking When Hot [Causes and How to Fix it]

Brake booster brake booster replacement

A brake booster is standard these days, but it wasn’t a few decades back. The location is between the brake pedal and the master brake cylinder. The purpose is to increase the pressure of the pedal and improve stopping power. It uses a vacuum from the engine, meaning the engine must run in order to have brakes. That’s why it is never a wise idea to turn off the car while going downhill. You will literally lose your brakes. This is a dangerous situation in which you can cause an accident. Your brakes may barely work, but this depends on a car.

Brake master cylinder

brake master cylinder replacementEach car has one of these cylinders. It is located on the end of the brake pedal, and it is used to distribute the fluid and pressure to all slave cylinders. They are present on each wheel, and they are responsible for braking. A master cylinder will usually have a brake fluid container, which does precisely as the name tells.

Read Also: What are the Symptoms of a Bad Brake Master Cylinder

Brake pedal

brake pedalThere is no need to mention this component. The brake pedal is a part of the brake system that is located inside the cabin. If you have a car with automatic transmission, you will have 2 pedals, brake, and a throttle. If you have a manual transmission, you will have three pedals. The brake pedal is in the middle. The other two are clutch and throttle. The size and shape of brake pedals will vary, and there are countless examples. In general, automatic transmission cars have a larger pedal than cars with manual transmission.

Read Also: Brake Pedal Goes to Floor When Engine Running [Causes and How to Fix]

Wheel Cylinders

rear wheel cylinder replacementIf you have read all of the points above, you know that all cars have one master cylinder and 4 slave or wheel cylinders. Their mission is to get the pressure and the fluid from the master cylinder using pipes and hoses and to apply the pressure to the brake pads or the brake shoes. The purpose might be the same, but these two cylinders don’t look the same. A caliper is the slave or wheel cylinder, while drum brakes use different cylinders located inside the drum. They are much smaller and have two sides that expand when you press the brake pedal. You can look for more details regarding parts of a brake caliper.

Brake fluid container

brake fluid containerAs the name suggests, this component contains brake fluid. Brake Fluid Color should be yellow or brown. Red isn’t an option and dark means that there is some issue with the system. You must remember that brake fluid is specifically designed for this purpose. It won’t compress, meaning it will be able to transfer the pressure to the slave cylinders. Ordinary oil will compress, meaning it won’t be able to transfer that pressure. You will lose brakes, and you won’t be able to stop. Air can compress as well, so it is mandatory to bleed the brake system while replacing some components, including the brake oil and brake oil container. Almost all containers have wiring leading to the top so they can detect when the brake fluid is below the minimum.

Brake hose pipebrake hose pipe

It is another component that does precisely as the name suggests. Brake hose pipe travels between the master cylinder and the slave cylinders. All cars have them, and in most cases, they are made from copper or brass. The goal is to withstand that pressure and not to corrode over time. These pipes are usually protected. They may pass through the inside of the car, and they are held in place. If this pipe breaks, you will have to replace it as soon as possible. Losing pressure and fluid means your brakes won’t work.

ABS Modulehow to test abs module

ABS meaning is an Anti-lock Braking System, and it does as you may believe. The main purpose is to prevent wheels from locking and skidding. All new cars have these modules, and they are more important than you may believe. A car will usually have sensors located on all 4 wheels. There will be one module located in the engine bay known as the ABS module, and it will record the data obtained from those sensors and the braking system. Then it will calculate when and how much force to apply in order to prevent skidding. You need a precise abs parts name to get a replacement part for your car.

You may like: How to Bleed ABS Module Without Scan Tool

Brake System Components Categories – YouTube

Frequently Asked Questions (FAQs)

Q: What does the brake system consist of?

Hydraulic brake system components are brake pedal, brake booster, master cylinder pipes, slave cylinders, brake pistons, pads, and rotors. This refers to cars that have disc brakes. The ones with drums have the first 4 components also, but additional ones include brake shoes and drums. This is an older and less efficient system.

Q: What are the two types of braking systems?

The two main types are dick and drum brakes. Drum brakes are older and offer less performance due to the friction which is caused between the drum and the brake shoes. Usually, old cars have this system or some new cars but only on the rear wheels. Disc brakes have rotors and calipers instead of drums and brake shoes. They are far more efficient. Both brake system parts and functions are identical.

Q: How braking systems in vehicles works?

The method is very simple. In a nutshell, when we press the pedal, the fluid will travel through the pipe and reach a caliper or a slave cylinder. It will apply pressure to the pads or brake shoes that will cause friction and slow down a car. All systems work in the same way, but their efficiency is different.

Q: Which brakes are better ceramic or semi-metallic?

In the lack of a better word, ceramic brakes are the best option. You can see them on high-end sports cars, and they are excellent due to two reasons. The first one is better friction while stopping, so a car will slow down faster. The second reason is heat resistance. Some of these systems can operate at a temperature of 1200 degrees Celsius. Semi-metallic systems are common in ordinary cars, and they are more affordable.

Q: How many types of disc brakes are there?

There are two main types. The first one is older and rarer these days. It is known as a floating system meaning that the brake pad piston will be present on one side only as such braking power id decreased compared to the opposite system, which has pistons on both sides. The pressure these two pistons can make is much higher and therefore provides better stopping.


These are all brake system components you have on your current car and the ones you will have on your future cars. There is no other stopping system, nor will it be invented in the near future. Make sure your car has perfect brakes all the time, and you will be able to stop whenever you want or have to.

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Hi There, I am R. Hasan Tito, a mechanic, and owner of this website. My friend and I created this website to share our knowledge, expertise, and experience with our fellow mechanics' community and car users. I am a specialist and certified automotive mechanic (Both Heavy Commercial and Private Cars). I have been working as a mechanic for over fifteen years. I worked for a long time at Global Rebound Automotive companies (Toyota, TATA, BMW, Nissan, TVs, and Others ) as a Mechanic and Mechanics Supervisor.

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