Description
Power Products 118181P is a pressure protection valve that isolates auxiliary air circuits — air suspension, accessories, cab leveling — from the primary service-brake reservoirs on heavy-duty trucks and trailers. With 1/4″ NPT inlet and outlet, a 70 PSIG closing pressure, and a 75 PSIG opening pressure, this aftermarket valve directly replaces Haldex/Neway 90554107, Velvac 32086, and Ridewell 1234761B000, preserving brake-system air in the event of an auxiliary-circuit leak.
Signs You Need a New Pressure Protection Valve
- Air suspension fails to inflate or holds inconsistent ride height
- Audible air leak at the valve body or fittings
- Primary reservoir pressure drops when an auxiliary circuit is in use
- Valve fails to close, allowing brake air to bleed into auxiliary circuit
Specifications
| Manufacturer | Power Products |
|---|---|
| Part Number | 118181P (90554107P) |
| Part Type | Pressure Protection Valve |
| Port Size | 1/4 in NPT (inlet and outlet) |
| Opening Pressure | 75 PSIG (minimum) |
| Closing Pressure | 70 PSIG |
| Weight | 12 oz |
| Application | Auxiliary / air suspension circuit isolation |
Cross References
This valve replaces or is equivalent to the following part numbers:
- Haldex: 90554107
- Neway: 90554107, 90560150
- Velvac: 32086
- Ridewell: 1234761B000
- Euclid: E4324
- Automann: 170.9055411
- Tectran: WM778A1
- Williams Controls: 118181, WM778A
Applications
This pressure protection valve is used to isolate auxiliary air circuits in:
- Heavy-duty truck air suspensions (Neway, Ridewell, Hendrickson)
- Trailer air suspensions and accessory air circuits
- Cab air-ride and seat-leveling systems
Verify your existing valve’s port size and pressure ratings before ordering to confirm fitment.
