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- Spring brake priority systems were approved with the FMVSS 121 rule in October 1992 & are the most common systems on tandem & tridem trailers with spring brake chambers. The valve immediately provides tractor supply air to release the spring brakes & the internal Pressure Protection Valve opens to also fill the air reservoir at approximately 80 psi.
- This valve also releases the spring brakes faster when the trailer air reservoirs are full because it uses both tractor supply air & trailer reservoir air pressure due to the valves relay feature.
- 4 delivery ports available, 2 downward facing & 2 side facing.
- Designed for use with 2,800 cu in jumbo &/or 1,400 cu in air reservoirs.
- Complies with all regulations of FMVSS 121 & CMVSS 121
- Dimensions: Height 3.51” – Width 2.88” – Depth 4.05” – Weight: 2.13 lbs.
- Mounting Hardware – See Air Valves & Related Products / Mounting Hardware
- Air Piping Diagrams – See Technical / Air Piping Diagrams, multiple diagrams are applicable.
- PLUG UNIT ASSEMBLY 110515 for pressure protection portion repairs, yellow shaded area
- PLUG UNIT ASSEMBLY 110705 for moveable seat portion repairs, blue shaded area
- Competitive Part Interchange Guide
