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WABCO · Air System
GTA-S4721950330
In stock · ships from Knoxville
This is an ABS modulator relay valve for trailer air brake systems.
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Verified fitment for 2 applications
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All confirmed applications for this part number.
Other applications
Other applications
Only for trailers produced April 1, 1999 or later with 12V bayonet-connector ABS; not for earlier systems or different connector types.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 4 of 4.
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It receives signals from the trailer's ABS control unit and precisely controls air pressure to the brake chambers to prevent wheel lock-up during hard braking. Designed for trailers with WABCO 2M/3M or 3M Enhanced Easy Stop systems manufactured after April 1999, it uses bayonet-style electrical connectors. A failing modulator valve often triggers an ABS warning light on the dash, causes pulling or uneven braking, and should be replaced to restore safe stopping performance.
Part Number: GTA-S4721950330
MODULATOR VALVE
Unit: ea
Dealer: Post Onsite
Compatibility, alternatives, and more
Parts commonly needed alongside air system
