Jun 12 2020

When should you Change the Brake Discs and Pads?

 

Making sure your braking system works properly and replacing it when the time is right will not only save you money in the long run. It can also save your vehicle, or even your life in an accident.

But how do you know when it's time to replace the discs or the brake pads ? What is the function of each one? Let's take a closer look and see why the state of both needs to be taken into account.

 

How do the Brakes of a Car Work?

When we press the brake pedal, it is levered to push a piston into a narrow cylinder with hydraulic fluid (master cylinder). The fluid moves down the line of the braking system, where it forces the caliper to press a pair of brake pads against a disc. This, in turn, causes the wheel to slow down .

The energy released by stopping the wheel is converted to waste heat, which must be dispersed. Because the disc has a relatively quick cool-down time, this type of brake offers better performance than drum brakes , and is widely used in today's vehicles. Considering the number of times we can apply the brakes during a car trip, it is not surprising that the pads and brake discs need to be replaced periodically .

 

What are Brake Discs?

Typically, a brake disc is an iron (or carbon composite if high-performance) disc that attaches to a car's suspension and is held by a brake caliper that houses the pads inside. brake. The friction between the disc and the pads is what stops the vehicle. The brake disc has numerous advantages over the drum, as it dissipates heat more quickly and, consequently, provides strong and constant braking power.

Disc brakes also give the driver more "feel" on the pedal, allowing him to modulate pressure more easily so he doesn't get too rough on the spot. In applications designed for maximum performance, a brake disc may be comprised of two discs joined (side by side) by several rotors. This, in effect, makes the disc “ventilated”, aiding in more optimal cooling .

 

What are Brake Pads?

The brake pads are a key part of the brake system of your vehicle; are located inside the clamps. Without the brake pads working properly, other elements of your car, such as the discs or calipers, will begin to wear down sharply.

Maintaining effective and efficient brake pads is important to avoid costly future repairs and unsafe driving conditions . So it is important to be able to identify when is a good time to change these parts.

 

What Happens when the Disc or Brake Pads Wear Out?

Every time you apply the brakes on your car you are causing minimal amounts of wear on the brake pads. For each type of pad (ceramic, organic, and metal), this friction causes small amounts of the protective coating that covers them to wear out. On the discs the case is similar. They can even have microcracks , ripples on the surface or multiple scratches of irregular shape.

Over time, this deterioration begins to build up: as the brake pads get thinner and thinner, they will eventually get to the point where they need to be replaced. However, it should be clarified that there is no exact period that determines when to do it, since it depends on the type of car, the time we drive it, where we drive it and how we drive it.

In this way, it is advisable to control the wear of the pads and change the brake discs from 25,000 km (although it can last up to 80,000 km). It is important to note that the front brakes suffer more than the rear brakes, so their wear is greater (up to two times more). Many are vehicles that have a warning light on the instrument panel that warn in advance that it is necessary to change the pads, but you can always do a visual inspection.

 

How do I know if the Brake System is Worn?

Checking the brakes to make sure they are in good condition requires the senses of sight, hearing, and touch. Together, they will give you a good idea of ​​when to replace the brakes. Here are a few signs to see if it's the right time:

• Squeaky Noise - It's normal that there is a bit of squeal coming from the brakes under normal driving conditions, depending on the cleanliness of the brakes, the materials used for your pads, and the weather. However, a loud screech is a warning that the brake pads may need to be replaced.
• Some pickups use a semi-metallic layer within themselves or an external sensor designed to emit that annoying sound as a warning. This noise can be heard even when the brakes are not used. If you wait too long at this point, there will come a time when the pads are completely worn out and potentially can lead to additional costs by damaging the brake disc.
• Warning Light - Some cars have a warning light on the dash to warn you when your brakes need attention. Most sensors have the same lifespan as the brake pads, so they must be replaced together. Before relying on this method, it is best to consult the user manual, as not all vehicles are equipped with such sensors.

• The Car is Shifting to one Side : If you feel that your car is shifting to one side or the other while driving, it could be a sign of brake pad wear or that the caliper or piston pins are stuck. The same occurs when braking with certain intensity. If, keeping the steering wheel straight, the car tends to roll to one side, the brake system needs an overhaul.
• Visual Check : It is a good idea to visually check the brakes regularly, for example, every 20,000 kilometers. It is extremely important if your car does not have sensors. You can visually check the brake pads by looking through the spokes of the rim. If they are less than 3 millimeters thick, then they must be replaced.
• Vibrations : If you feel your vehicle vibrate while braking, it is a sign that the brake discs may be abnormally worn or have suffered thermal damage after heavy use of the system.