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Knox Trailers · Brakes & Wheel End
ACF6404-906
In stock · ships from Knoxville
This is a slack adjuster for heavy-duty truck air brake systems.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
We don't publish fitment for this part yet. Rather than guess, get it confirmed against your truck in under a minute.
It adjusts the distance between the brake shoes and the drum, compensating for lining wear to maintain proper brake stroke. Designed to fit a 1.5-inch diameter camshaft with 10 splines, it provides an arm span of 5.5 to 6.5 inches. Replace it when the adjuster fails, seizes, or can no longer maintain correct pushrod travel, which helps prevent brake drag and ensures safe, even braking.
Part Number: ACF6404-906
SLACK ADJ 10SPL 5.5 & 6.5
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
