When you press the brake pedal, the force is transmitted through the master cylinder, generating hydraulic pressure. This pressure travels through the brake lines to each brake assembly, including the drum brake system. Within the drum brake assembly, the brake cable is pulled, which then activates the lever. As the lever moves, it pushes the brake shoes against the drum, effectively slowing down the vehicle.
However, drum brakes do have their downsides. One significant drawback is their tendency to overheat. When subjected to prolonged or heavy braking, drum brakes can suffer from brake fade, where the braking performance diminishes significantly. This issue is exacerbated under high-stress conditions, such as aggressive driving or towing heavy loads. Additionally, the maintenance of drum brakes can be more cumbersome as they require more frequent adjustments than disc brakes.
The brake drum is a circular metal component that houses the brake shoes in a drum brake system. When the driver presses the brake pedal, hydraulic fluid is sent to the brake cylinders, forcing the brake shoes outward against the inside surface of the drum. This friction slows down the wheels, bringing the vehicle to a stop. In trucks, where stopping distances can be significantly longer, the efficiency of the brake drum is crucial.