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Vehicle Safety Manufacturing · Electrical & Lighting
918Y998
In stock · ships from Knoxville
Heavy-duty turn signal switch for Western Star trucks, designed as a direct replacement for OEM part 84401-3431.
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Verified fitment for 1 applications
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Western Star
Western Star
Exact model years and chassis are not detailed in available sources. Verify fitment by matching your existing OEM number 84401-3431 before ordering.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 8 of 8.
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It operates on 12 volts and combines turn signal, hazard flasher, high/low beam dimmer (lift-to-dim), and stop lamp circuitry in one unitized assembly. Typically replaced when the original switch fails due to worn contacts, broken hazard tab, or loss of detent feel. Meets SAE and FMVSS108 specifications for reliability and driver feedback.
Part Number: 918Y998
WS TURN SIGNAL SWITCH
Vendor: Velocity
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside electrical & lighting
