|Drum brake system
||The primary components of the drum brake system are: the backing plate, the brake drum & brake shoe assembly, the wheel cylinder, retaining clips & springs and automatic brake self-adjuster.
|Drum brake operation
||The drum brake system operates by forcing the friction-lined brake shoes against the inner surfaces of the rotating drums. The shoes are designed to operate with a self-energizing action.
|Brake linings & shoes
||The brake lining is a specialized friction material, riveted or bonded to a steel shoe. The shoe transfers the wheel cylinder movement and forces the lining against the rotating drum.
||The backing plate is bolted to the axle housing or suspension member. It provides a mounting for the wheel cylinders and brake shoes to act against the rotating drum.
||The wheel cylinder and piston react to hydraulic pressure from the master cylinder, and the outward movement of the piston forces the shoe and lining against the drum.