20560349
Non-Return Valve
Mack

A one-way valve that prevents backflow in the air or fluid lines of heavy-duty Mack systems, this non-return valve contributes to system integrity under high-pressure conditions. By ensuring that pressure is maintained in the appropriate circuits and that contaminants or residual fluids do not travel backward, it supports consistent braking response, efficient engine breathing, and reliable pneumatic control. The valve’s seals and seating surfaces are engineered for durability against vibration, temperature swings, and exposure to lubricants or coolants common in heavy-truck environments. Replacement helps preserve proper circuit isolation, reduces the risk of pressure surges, and supports predictable operation during rapid throttle changes or stop-and-go driving. Proper installation includes verifying orientation and securing connections to prevent leaks. Source One Parts Center offers this essential component for Mack applications as a dependable maintenance option.