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Knox Trailers · Air System
800405P
In stock · ships from Knoxville
The 800405P is a 12-volt purge valve assembly designed for Bendix AD-9 air dryers found on heavy-duty trucks.
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Fits any heavy-duty truck or bus using an AD-9 style air dryer; no vehicle-specific restrictions.
Part data verified against 4 catalog sources
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It controls the expulsion of moisture and contaminants from the air system during the dryer’s purge cycle, and includes an integrated heater and thermostat to prevent freezing in cold weather. This complete assembly replaces the entire purge valve housing, soft-seat piston, and heater, and is typically installed when the original valve leaks, fails to purge, or the heating element burns out.
Part Number: 800405P
12V PURGE VALVE ASSY.
Unit: ea
Dealer: Knox Trailers
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Parts commonly needed alongside air system
