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WABCO · Air System
R955320
In stock · ships from Knoxville
This is a genuine WABCO trailer ABS valve and electronic control unit (ECU) kit.
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Verified fitment for 1 applications
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All confirmed applications for this part number.
Universal fit
Designed for trailers with WABCO ABS systems. Supports multiple sensor/modulator layouts: 2‑sensor/2‑modulator (2S2M), 4‑sensor/2‑modulator (4S2M), and 4‑sensor/3‑modulator (4S3M).
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 8 of 8.
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It includes the modulator valve (part number 4005001030), the ECU, and a power cable to manage anti-lock braking on heavy‑duty trailers. During a stop, the ECU monitors wheel speed sensors and commands the valve to modulate air pressure, preventing wheel lockup. The kit is typically replaced when the ABS warning lamp signals a fault or the modulator valve fails to control brake pressure correctly, which can cause wheel lock or uneven braking.
Part Number: R955320
ABS ECU VALVE
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside air system
