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Sealco · Air System
110257-nl
In stock · ships from Knoxville
This is a pressure protection valve used in heavy-duty truck and trailer air brake systems.
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Verified fitment for 4 applications
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All confirmed applications for this part number.
Other applications
Other applications
Always install with the vent port facing downward. This valve is used in conjunction with a relay emergency valve (such as Sealco 110338 or 110376) and does not function as a standard pressure protection valve.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 3 of 3.
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Its main job is to hold at least 70 PSI of air in the supply line while allowing air to flow to the emergency or parking brake side, even when supply pressure drops. It's commonly installed on converter dollies, lift axles, and other axles that don't have spring parking brakes, where it helps meet the requirement to keep supply line pressure above 70 PSI. Replace it when you have air leaks from the vent, parking brakes that won't release, or if the valve fails to maintain the minimum 70 PSI threshold.
Part Number: 110257-nl
pressure protection valve
Dealer: Post Onsite
Compatibility, alternatives, and more
Parts commonly needed alongside air system
