Car Brakes 101: Essential Know-How for Ensuring Reliable Stopping Power

Braking system failure is one of the most common factors in fatal car accidents, so when was the last time you had yours checked? If you’re driving on worn or damaged brakes, you’re putting yourself, your fellow passengers and other traffic participants at risk. 

Instead of waiting to be caught off guard by a squeaking noise or a light show of warning lights on your dashboard, you need to regularly inspect, service and maintain your brake assembly. Ensuring reliable stopping power at all times is one of the invaluable safe driving tips that can save your and other people’s lives.

To do this, you need to know a thing or two about how cars brake and how all those parts work in correlation to safely slow down your vehicle. Of course, you’ll need to find a reliable mechanic to check and service the brakes, but a little know-how on your end will help you determine when’s the right time to replace your car brakes before it’s long overdue.

disk brakes

How Do Car Brakes Work? 

Since the early 1940s, virtually all vehicles incorporate hydraulic brake systems. These automotive brakes transform and amplify the force applied to the pedal to change the mechanical energy into heat. Through a lever-like motion, the pedal, along with the brake booster, increases the force on the brake fluid in the master cylinder. 

Here, the master cylinder further enhances the fluid pressure and sends it to the callipers and wheel cylinders through the lines and hoses. As a result of the pressurised fluid acting on the calliper piston, the disc brake pads are squeezed inwards to clamp the pads against the rotors. 

This generates friction and heat, which slows down the rotor and wheel movement, causing the vehicle to come to a stop. In drum brakes, the heat-friction is generated by the wheel cylinders sliding outwards, thus forcing the brake shoes against the drum.

sports car

The Main Parts of the Braking System

Vehicle brakes are comprised of many parts. Some of the important components in your braking system are the master cylinder, the power brake booster and the brake lines and hoses. The other key parts involved in the process will differ depending on whether your car has a disc or drum brake assembly.

Disc brake assemblies incorporate brake callipers, brake pads and disc rotors. Considered to be superior in terms of design and performance, disc brake assemblies are found on most modern vehicles. 

Although they use the same principle to slow down a vehicle, drum brake assemblies are far more complex in terms of construction, featuring a brake drum, brake shoes, wheel cylinders, backing plate, return springs, adjuster mechanism and other mounting hardware.

car brakes mounting

How Do You Know If Your Brakes Are Bad?

Automotive brakes are subjected to heavy use, so even the most expensive and durable parts will show signs of wear over time. Brake failure or damage is often accompanied by tell-tale signs that shouldn’t be ignored. 


Squeaking noises are your car’s way of telling you that the brake pads might need replacing. The brake pads are engaged each time you brake, and this causes them to wear thin. If you hear this audible warning, that’s your cue to visit a mechanic. It’s better to be safe than sorry. 

Should you ignore this sound, you may soon notice a much louder grinding noise caused by metal-on-metal contact. This means that your pads have completely worn down, and the callipers are pushing against the rotors. In some cases, the rotors can be repaired, but if there’s excess damage on their surface they might need replacing.


If your steering wheel or brake pedal vibrates when you’re trying to slow down or stop, it can be a warning sign of badly rusted or glazed rotors or drums. The vibration may also be caused by dirt or oil in the brake linings. 

Spongy Feel 

If the brake pedal response feels mushy or requires more force to be exerted, you may have a problem with the hydraulic system. A leaking brake line or insufficient brake fluid in the master cylinder can cause the brakes to fail when you apply them, so don’t risk it and get it checked ASAP. 

Visual Signs 

A significant brake problem may activate your “check brake” or “ABS” light on your dashboard, so don’t ignore it even if it doesn’t stay illuminated. Address the issue as soon as possible to ensure that you can safely operate your vehicle.

worn car brakes

How Often Should You Change Brakes?  

Do you need to wait for these signs to show to replace your brakes? Of course not. To keep wear to a minimum, you should have your brake pads replaced after approximately 80,000 km. As for the rotors, these can soldier on for up to 100,000 km. This will greatly depend on your driving habits and the quality of the parts. In some cases, these assembly components will need replacing just after 40,000 km, so it’s vital to keep close tabs on your system.