Description
WM778A-G - PRESSURE PROTECTION VALVE - NEW
PART NUMBER(S):
Fleet Products: WM778A-G (New) | Replaces OE: Spicer: WM778A, 118181, 378414 | Williams Controls: WM778A1 | Haldex: KN31000, KN31001 | Automann: 170.90554107 | Meritor: R955KN31000X | PAI: EM36850 | Neway: 90554107
DESCRIPTION:
Model: Pressure Protection Valve
Vehicles: Heavy-duty trucks and trailers with auxiliary pneumatic systems supplied by the primary air system
• Valve Type: Normally closed pressure protection valve
• Inlet Port: One 1/4" NPT
• Outlet Port: One 1/4" NPT
• Opening Pressure: 75 PSI
• Closing Pressure: 70 PSI
• Maximum Operating Pressure: 150 PSI
• Operating Temperature Range: -40°F to 180°F (-40°C to 82°C)
• Function: Isolates auxiliary air circuits to protect primary air brake system pressure
Applications:
Designed for truck and trailer air systems where auxiliary equipment is supplied from the primary air reservoir. The valve prevents airflow to the auxiliary circuit until adequate pressure is available and closes if system pressure falls, protecting the primary brake air supply from auxiliary-system leakage or failure.
CROSS-REFERENCE(S):
15293, TC WM778A1, TCWM778A1, TEC-WM778A1, TECWM778A1, WM778A1TEC, AC008, 032086, 1234761B000, 15292, 170.90055411, 170.KN31000, 31MT15759, 32086, 334-1146, 36502-2, 401207, 6451005, 90054017, 90054107, 9054107, AM17090554107, AVKN31000, CHE-378414, E4324, E-MDKN31000X, HM1PPV, K861008, M118365, R986039, S-C088, SC088, SGR-378414, STU-SC088, TDAR955KN31000X, TQ15292, VS1128, WA118181, WA118365, WA378414, WAKN31000, WAN60007, WM778, WM778100, WM778AN, 90560150, N15759DB, 118365, 20QE2128, WIL118181, ZDA118181, TCT-WM778A, WIM118181, WM-778-A
A cross-reference listing means this part may be a suitable replacement for the listed part numbers. Always verify fitment before installation.
IMPORTANT INSTALLATION NOTES:
✔ Confirm the valve has two 1/4" NPT ports and identify the inlet and outlet before installation.
✔ Install between the protected primary air supply and the auxiliary pneumatic circuit.
✔ Verify the application requires a 75 PSI opening and 70 PSI closing pressure.
✔ Apply air-system-compatible thread sealant without allowing sealant to enter the valve.
✔ Charge and leak-test both circuits, then verify the auxiliary supply closes as pressure drops.
Warranty Information
