What are Brake Pads and Rotors?

As an essential safety feature for your vehicle, your brakes couldn't be more important. Best practice is to check brake pads about once a year, or every time you have your tires rotated. But safe braking involves more than just pads. Take a look at eight parts that you should replace when you get new brakes.

What Are Brake Pads and Rotors?

1. What Are Brake Pads?

Brake pads do a lot of work to stop your car and tend to need the most attention. The friction material on the brake pad will wear down over time and use. You’ll know the brake pads are ready to be replaced if you experience any of these conditions:

  • Decreased braking performance: As the brake pad friction material wears thin, braking efficiency can decrease, leading to increased stopping distances. This can be dangerous as an extra foot or two of braking distance can be enough to cause an accident. Inspect the brake pads and entire braking system if you are suspicious of this condition.
  • Squealing: This noise is there for you. It’s not fun to hear, but the pads have a metal sensor that’s made to squeal when they are almost worn out. Some vehicles are equipped with electronic brake pad sensors. When the pad wears down, the sensor will turn on a dash warning light.
  • Grinding: If you hear a grinding sound most likely the brake pad metal backing has come in contact with the brake rotor because of worn friction material. Immediate attention should be given to the brake system. At this time, you should consider brake pad and rotor replacement. The extra money spent to ensure the best braking performance could make a life or death difference in sudden stopping situations.

When you replace brake pads, don’t forget about the brake hardware. These components ensure the brake job is done right. Some brake pads come with new brake hardware.

2. What Are Brake Rotors?

Disc brake systems, which usually appear on the front two wheels of a vehicle (and often the rear as well), use brake rotors. The brake rotor attaches directly to the steering spindle or wheel bearing hub assembly. When brake pads apply enough pressure to the rotors, they slow or stop the vehicle. Brake rotors are subject to extreme pressure and temperature during braking, so ensuring you have well-maintained and high quality rotors is key to braking safety.

3. What Are Brake Calipers?

Part of the disc brake system, the caliper holds the brake pads in place. The caliper is a part of a hydraulic system where the brake fluid pushes a piston in to the brake pads, against the brake rotor, stopping the wheel.

4. What Are Brake Drums?

Many vehicles have drum brakes in the rear. The friction between the brake drums and the brake shoes assist in slowing or stopping the vehicle. Worn brake drums should always be replaced. Don’t forget to replace the brake shoe hardware and wheel cylinders at the same time. Old wheel cylinders can develop a leak afterwards and create a dangerous braking situation.

5. What Are Brake Shoes?

Brake shoes are integral parts of drum brakes. Since they work by transferring kinetic energy to thermal energy, brake shoes create tons of friction, can get incredibly hot, and wear down over time. Because this friction is largely responsible for stopping your vehicle, making sure the brake shoes are in good shape by performing routine inspections such as when the tires are rotated.

6. Master Cylinders and Wheel Cylinders

Master cylinders and wheel cylinders both control pressure via a combination of pistons and brake fluid. Since these parts interact directly with brake lines, they can fail if you don’t maintain fluid levels or if you use a brake fluid that isn’t compatible with the brake system.

7. What Are Brake Boosters?

These components amplify the pressure you apply to the brake pedal and can improve your ability to slow or stop quickly. Without a brake booster, you may have to apply more than twice the normal pressure to stop your vehicle.

8. Brake hoses and Lines

Hydraulic brake hoses and lines run from the master cylinder to each wheel. These parts hold the brake fluid and extreme hydraulic pressure when the brakes are applied. These brake components are subject to road debris, salt and other elements that can cause damage and lead to failure. Over time, brake hoses develop cracks and tears. Failure of a line or hose will cause catastrophic failure. They should be routinely inspected and replaced as necessary.

9. What is brake hardware?

Brake hardware consists of the metal abutment clips that the pads slide on inside of the caliper bracket. While they do not look like a wear item, they are spring loaded parts that lose their tension over time. When worn, they create vibrations that is heard in the form of brake noise and low stopping speeds. These clips should be replaced when replacing pads or pads and rotors.

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