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Haldex · Air System
A1000SX
In stock · ships from Knoxville
This is a remanufactured emergency relay valve originally designed by Sealco for pre-FMVSS 121 air brake systems.
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Verified fitment for 3 applications
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All confirmed applications for this part number.
Other applications
Other applications
For use only on brake systems manufactured before the FMVSS 121 mandate; not compatible with modern ABS-equipped trailers.
Part data verified against 5 catalog sources
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It regulates air pressure to the service brake chambers during emergency applications, ensuring sufficient braking force on converter dollies and older trailers. Replace this valve if you experience inconsistent brake response, air leaks, or failure to hold reservoir pressure, as wear can compromise trailer braking safety. Remanufacturing restores it to OE specifications with new wearable components.
Part Number: A1000SX
RELAY EMERG VALVE
Unit: ea
Dealer: Post Onsite
Compatibility, alternatives, and more
Parts commonly needed alongside air system
