How Does a Disk Brake Pad Work?

Most disk brake pads are made from highly-refined, semi-metallic metal. These types of disk brake pads, which are pretty standard on most passenger cars and trucks, are highly wear-resistant and effective at reducing friction generated heat between the disk brake pads and disk brake rotors. Disk brake pads are engineered to withstand high heat and friction.

On cars that have both a disk brake and drum brake, the disk brake performs the majority of the stopping power. Normally, a disk brake will be in the front of a vehicle, and the drum brake will be in the rear. The reason for this is due to the fact that when a car's brakes are applied, the majority of the car's weight is transferred towards the front of the car, which applies much greater strain and force to the front brakes. A disk brake pad handles roughly 70 percent of a car's stopping power. Therefore, a disk brake pad, although highly wear-resistant, wears out much sooner than a standard drum brake.

The squeezing action of a disk brake pad against a disk brake rotor is made possible by hydraulic brake fluid. Instead of using a cable to manually squeeze the brake pad against the rotor, hydraulic brake fluid is used to supply the squeezing force. Brake fluid lines route the hydraulic brake fluid into each disk brake caliper, where the pressurized brake fluid pushes against the brake pads, causing them to move, or squeeze, against the disk brake rotor.