What You Need To Know About Brake Pads

Brake pads are part of a disc brake system and are essentially a flat piece of metal with friction lining on one side. The friction lining is responsible for creating friction between the pad and the rotor which helps slow down and stop the wheels. 



The Brakes in your cars are resilient and hardworking systems that work towards countering the forward energy of the car and bringing you to a stop safely. Brake pads are an important part of the modern disc brake system. Brake pads functioning is fairly simple to understand - they clamp the brake rotors or discs which are mounted to the rotating wheels, and this stops the wheel and ultimately the car. The disc comes to a stop due to the effect of friction between the brake pad surface and the brake rotor. Brake pads are integrated into the brake calipers that are part of a hydraulic system that transfers the brake pedal movement to the brake pads. Here’s a brief on how the disc brake system works:

• When the brake pedal is depressed, the brake master cylinder is actuated usually through the brake power booster that pressurizes brake fluid. 

• This hydraulic pressure within the brake lines is transferred to the brake caliper which houses a piston. The piston expands within the caliper. 

• The brake pads are connected to the pistons either directly or indirectly depending on the type of caliper assembly. There are two pads surrounding the brake rotor, clamping on it from both ends. 

• As the piston moves, the brake pads are forced against the brake rotors, 

• The friction between the brake pad and rotor slows down the wheel and brings the car to a stop.

• The harder you push the pedal, the more force is applied to the brake pads, and the greater is the friction. This increases the rate at which the vehicle slows down but also generates more heat. However, the ABS system plays an important role in modulating the brake force to maximize stability and safety while braking. Learn more about the ABS system's functioning in this article. 

Friction is detrimental for any mechanical system, however, effective use can help us in many ways but at a premium price. What that means is although we are able to use the force of friction to stop the vehicle, we need to compromise or compensate by sacrificing brake pads in order to effectively brake every time. When a vehicle is brought to a stop all the energy of the moving vehicle is almost completely converted into heat energy. This heat energy is felt at the rotor and the brake pads and can reach upwards of 450℃. This amount of heat is able to melt most materials and so brake pads need to be made of hardwearing elements that can withstand heavy stresses and temperatures and also last long. This is why there are many types of brake pads materials used today like metallic, ceramic, and organic. 



Being able to stop your automobile quickly is more essential than acceleration. That's why choosing the right brake pad for your vehicle is important. There are various types of brake pads materials used, mainly organic, ceramic, and metallic. If you want to know which brake pad is best suited for your vehicle then refer to the “Which Brake Pads Is Right For My Vehicle” section in our brake pad buying guide. 



The brake pads are essential to every disc brake system and their failure can indicate many different signs before the vehicle is at risk of complete brake disability. Always make sure to take immediate action when it comes to brake system failure in your vehicle. Here are a few significant symptoms experienced when brake pads fail:

1. Reduced Braking Effect: The most prominent sign indicating bad brake pads is the slow or reduced braking effect. The brake pads are responsible for stopping the rotor and if the brake pads are worn out then you can expect reduced braking effect and increased braking distance. 

2. Soft Or Spongy Brake Pedal: Uneven or severely worn-out brake pads have the tendency to cause a spongy response on brake pedal operation. Severely worn-out brake pads will also require you to press the brake pedal harder and further to effectively brake which is indicated by a soft brake pedal. 

3. Annoying Sounds from the Brakes: Some brake pads come with a brake pad wear indicator in which once the brake pads are completely worn out, a metal disc comes in contact with the rotor causing a squealing noise due to metal-on-metal contact. Grinding noise is another sound that may emanate from the brakes when there is the presence of dirt, gravel, or rocks on the caliper or disc causing grinding noises when brake pads come in contact. 

4. Vibrations While Braking: If the brake pedal, steering wheel, or tires seem to wobble or vibrate when the brakes are applied then there may be a problem with the brake pads or rotors. The brake pads can wear unevenly or chunks of brake pad material can break off or get deposited on the rotor surface permanently and when the brakes are applied this uneven surface of the rotor comes in contact with the brake pads causing vibrations. This can also be caused by warped rotors. 

5. Vehicle Pulling to One Side: The brakes are applied with even pressures to both corresponding wheels and the distribution of the braking force is equivalent. When the vehicle pulls to one side or causes uneven braking, it indicates that the brake pads may be worn out unevenly in adjacent wheels.

6. Pungent Or Burning Smells: Burning or pungent smells may be a result of overuse of the brakes which push them to their limits causing extreme heat in the brake pads. This can be particularly dangerous since avoiding to stop and allowing time to vent and cool off the brakes can cause the brake fluid to heat up to its boiling point and result in complete brake failure. 

7. Brake Warning Light: If the brakes are worn out, a brake light is illuminated in the dashboard indicating potential brake failure. The previously mentioned squealing noise is due to a mechanical brake wear indicator. Electronic brake wear indicators sense the amount of brake material left and send a signal which alerts the driver to the brake pad condition. Some less advanced systems simply show a warning light when the brake pads need replacement. There may also be an electronic noise generated if the brake pads are worn completely and urgently need to be replaced.  

In case you are experiencing one or more of the above symptoms then take a look at your brake pads and have them replaced immediately. 



Brake pads are the most vulnerable and overworked part of a disc brake system and need to be replaced often so that you can continue braking without issues. But how do you know if you need to replace your brake pads? Here are a few ways you can identify worn-out brake pads:



Electronic Indicators: Advanced electronic wear indicators on the brake pad sense the wear on the pads and send a signal to the ECU which tells the driver in the dash about the brake pad condition. Some less advanced systems simply show a warning light when the brake pads need replacement. There may also be an electronic noise generated if the brake pads are worn completely and urgently need to be replaced.  

Some cars have no wear indicators and you must rely on other methods such as this for determining brake pad condition. A visual inspection of the brake pads can be done without removing your wheels but this may be less accurate. 

• Start with your front wheels. Turn your wheels outwards and look at the brake caliper. 

• Once you have a good view of the caliper look for black brake pads. You need to see the thickness of the brake pads since the thinner the pads the more important it is to replace them.  

• Another way is to insert a straw and check the thickness. This can only be done in an open-wheel setup (rims that have large openings to view the pads). 

• Start by inserting a straw perpendicular to the disc. Insert it between the brake pad until it hits the rotor. Mark the location where it touches the brake pad. 

• Now measure from the end of the straw to the marking and subtract the 5 mm to compensate for the backing plate thickness. 

• The resulting measurement is the approximate thickness of your brake pads. It is recommended to replace brake pads if their thickness is less than 4 mm. (new brake pads have a thickness ranging from 12-15 mm). Use the same method on your rear wheels as well. 

  
  

The more accurate method of determining brake pad thickness is by removing the wheels and calipers and examining the brake pads themselves. This isn’t very complicated either and only requires a few tools. First, loosen the lug nuts using an impact wrench or breaker bar. Then hoist the car up on jack stands. Now remove the wheel and using a ratchet and the appropriate socket remove two bolts on the caliper. The brake pads are now exposed. Examine the condition of the brake pads. It is good to measure them using vernier calipers for the best results. Alternatively, you can measure them using a scale. Replace them if the thickness of the friction materials is less than 4 mm. Anything less than 4mm is very critical and can cause reduced braking performance and compromised safety. 



This method is not precise but can be an indicative sign for many cars and a quick look doesn’t hurt anyone. Pop your hood and examine the brake fluid level. If it has fallen drastically below the marked location then you may have severely worn-out brake pads. This is because the pistons are pushed forward as the brake pad materials wear off. This forward movement of the piston means that the fluid has to travel more for piston engagement and therefore the fluid level drops. Note that for this method to work, there have to be no brake fluid leaks or you may be looking at a different issue altogether. 

These are the methods for determining worn-out brake pads. It is recommended to always inspect the braking system regularly before any problems occur and show symptoms of failure. However, you can look out for the signs of brake pad failure that will signal you that it is time to replace your brake pads or rotors.



Your brakes service schedule can vary depending on many factors but you need to inspect the brake components regularly. It is a good idea to check your brakes during every oil change or at least every 15,000 km. If you notice any symptoms of brake pad failure then carry out an inspection as soon as possible. 



The replacement process for brake pads can be a little complicated for a newbie or someone with less experience working on cars. However, with the right set of tools and a detailed guide you can try changing your brake pads. Here is a step-by-step guide on replacing brake pads yourself. Make sure you refer to your service manual for vehicle-specific replacement procedures.