The Bendix® ES™ extended service foundation drum brake is used in various applications on axles of commercial vehicles, providing the service and parking brake function. With all types of drum brakes, friction forces are generated by the internal brake shoes being pressed against the inner surfaces of the brake drum by the force generated by a cam. Due to their almost completely sealed housing, the brake shoes are well protected against corrosive influences (water, salt, and dust) and dirt (sand, stones, and mud), even when driving on rough terrain. With the S-Cam brake, the cam and camshaft are rotated as a result of the force of the brake actuator acting on the slack adjuster. The brake shoes with brake linings are thereby pressed against the brake drums.