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KP Services Crossville · Brakes & Wheel End
ACF6404-905
In stock · ships from Knoxville
This is an automatic slack adjuster for heavy-duty 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 connects the brake chamber pushrod to the S-camshaft and maintains proper brake shoe clearance by automatically adjusting as the linings wear. This unit features a 1.5-inch diameter camshaft with 28 splines and a dual-pattern arm that can be used in either 5.5-inch or 6.5-inch span configurations. It is typically replaced when the internal adjustment mechanism fails, the splines are stripped, or the adjuster no longer holds proper stroke.
Part Number: ACF6404-905
SLACK ADJ 28 SPL 5.5 & 6.5
Unit: ea
Dealer: KP Services Crossville
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
