The Wabco 9253920090 double diaphragm is a genuine Wabco air brake part from Pro Gear and Transmission. Double diaphragm units of this kind combine a service section that applies the brakes from the pedal with a spring section that provides emergency and parking braking. Air pressure working on the second diaphragm keeps the heavy power spring compressed so the brakes stay released while driving, and if that air is lost the spring applies them. A secondary diaphragm that leaks often announces itself with a constant hiss of air at the dash valve exhaust once the parking brakes have been let off. Call us to confirm proper fit for your application.
Features
Wabco double diaphragm, part number 9253920090
Service section and spring section combined in one unit
Spring applies the brakes if air pressure is lost
A constant air hiss after the parking brakes are let off can point to a leaking secondary diaphragm
A genuine Wabco part from Pro Gear and Transmission
