What Kind of Brake Pads Should I Buy?
What’s in a brake pad? Your safety and security for one. Cars need to do two things more than anything else, stop and start, and the pads on front-wheel or four-wheel disc brakes make sure your car stops moving when you want it to. But what’s in a brake pad? Why are they so important, and why do we have so many different types?
Brake Pads Explained
1. What is a Brake Pad?
Brake pads use friction to stop your vehicle. They rest inside a caliper and clamp on the brake rotor as a reaction to pressure you apply through the brake pedal. This clamping on the rotor creates friction, which slows and stops the rotor, the wheel and the vehicle. This friction generates heat and “dust,” tiny shavings of the pad that come off when the brakes are applied. Modern pads are typically made from a semi-metallic or ceramic compound, and carry a few differentiating features like slots and chamfers.
2. Semi-Metallic Brake Pads
Semi-metallic pads are made from a 30%-60% metal by weight composition that includes other materials such as graphite lubricant. Semi-metallic or Semi-met pads are excellent performers under pretty much any weather condition, and provide a firm braking feel. Because they come in a lot of compound varieties, you can find a quality pad of this type for daily street driving or hard performance braking. While semi-met pads are known for great performance and durability, they can also produce a large amount of dust, and are a bit noisier than ceramic pads due to added metals.
3. Ceramic Brake Pads
The smooth, sophisticated choice, ceramic pads are known for their easy, quiet stops, and long-lasting performance. Made from a dense ceramic material, ceramic pads are favored for their quiet stops and consistent, all-around brake performance. Ceramic pads produce less brake dust. Most ceramic dust is vaporized by friction with the rotor, and the remaining dust is finer, lighter-colored and has a lower tendency to stick to wheels than dust from a semi-met pad. Although slightly more expensive, ceramic pads may be the best choice for day-to-day driving, but are not usually recommended for heavy duty hauling or aggressive braking. They also can under perform in cold temperatures, lacking, “cold-bite,” or immediate braking performance in extreme cold.
4. What is a Chamfer on a Brake Pad?
A chamfer is the angled edge of the brake pad. It controls the way the pad applies friction to the rotor, and significantly reduces braking noise.
5. What is a Brake Pad Slot and Why Does It Matter?
The slot in the middle of a brake pad increases braking performance by separating braking friction into separate components, and providing a small gap for gas dust, and heat to escape when friction occurs.
6. What is a Brake Shim?
The shim is a plate fitting between the pad’s backing plate and the caliper. Shims are generally made of multiple layers of steel and rubbers to reduce vibration that often causes brake noise.
When deciding on which brake pad you need, use the characteristics above to help decide what best fits your driving style. If driving mostly in extreme weather or mountain areas, or often tow and/or brake aggressively, semi-metallic pads are a great solution. If you are looking for less aggressive braking with quiet stops and cleaner wheels, a ceramic brake pad will meet these demands. You can get the parts you need at your local AutoZone Store. If the job is too big for you, seek out one of our Preferred Shops to help you do the job.