Drum Brakes: Why Are They Still Being Used Today? - The Cheat Sheet
All cars have rear brakes to help them stop, and while the two most commonly used types of braking systems vary differently in how they apply stopping force, they carry the same genetic make-up. Rotors (or discs) get grabbed by a set of pads that are wedged between a vice-like clamp called a caliper, and the harder you press the brake pedal, the harder that caliper squeezes the pads against the spinning rotor. Exposed to the air, these discs are often vented, and since they run cooler due to being exposed to the elements, they typically offer the greatest stopping power and longevity. But since the majority of a vehicle’s stopping power needs to be in the front, most automakers left the rear brakes drum-based. Some performance models saw disc brakes all around, but everyone else got drums in the rear, and even today you still see drums on certain new cars. The term “drum brake” refers to the barrel in which the brake components are housed, which like a rotor setup, is attached to the car’s wheels and hubs. Inside the drum is a set of “shoes” that get forced against the insides of the housing, courtesy of a complex array of springs, tensioners, and wires. Like pads, the shoes are made from a heat-resistant friction material similar to that used on clutch plates, and over time they will wear down and need replacing. Source: www.cheatsheet.com
