Theory

• A vehicle's brake system works on the basic principle of friction. By applying friction to moving wheels, momentum is dissipated and the wheel slows, eventually coming to a stop. This friction creates heat which contributes to system wear and failure. The rate of braking and heat dissipation depends on vehicle weight, braking force and the braking surface area.
  
  

Components of a Disc Brake System

• In a disc brake system, as force is applied to the peddle, the master cylinder distributes an incompressible hydraulic brake fluid to the brake. The fluid flows into the caliper, activating a piston that squeezes the brake pads against the disc. This friction slows the wheel and stops the vehicle. The components of a disc brake system are exposed to air and dissipate heat more efficiently than a drum system, slowing wear and prolonging system life.
  
  

Components of a Drum Brake System

• In a drum brake system, as force is applied to the peddle, the master cylinder distributes an incompressible hydraulic brake fluid to the brake. As the fluid fills the drum, the brake shoes are pressed outward, exerting friction to slow the wheels and stop the vehicle. The enclosed drum is prone to heat buildup and faster wear and failure.