S-42278-U or S42278U Hendrickson Brake Chamber is the air-powered actuator at the wheel end. Air pressure flexes a diaphragm inside the housing, the diaphragm drives the push rod against the slack adjuster to apply the brake, and a return spring pulls everything back when the air is released.
A leaking diaphragm lets air escape and weakens the brake, and a push rod that will not fully retract or a wheel end that runs hot are cues to look at the chamber and its slack adjuster. A genuine Hendrickson part from Pro Gear and Transmission. Call us to confirm proper fit for your application.
Features
Hendrickson brake chamber, part number S-42278-U or S42278U
Diaphragm and push rod design that applies the brake from air pressure
Return spring releases the push rod when air is exhausted
A leaking diaphragm or a push rod that sticks out signals it is time for service
A genuine Hendrickson part
