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Fruehauf · Brakes & Wheel End
ACF6404-1
In stock · ships from Knoxville
This is a manual slack adjuster for heavy-duty air brake systems.
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Verified fitment for 2 applications
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All confirmed applications for this part number.
Other applications
Other applications
Verify camshaft diameter (1.6") and spline count (37) before ordering. Manual adjustment is required; auto-slack versions are not interchangeable.
Part data verified against 4 catalog sources
Numbers this part supersedes or interchanges with. Showing 16 of 20.
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It connects the brake chamber pushrod to the camshaft, converting linear motion into the rotational force needed to spread the brake shoes. Designed with a straight arm, a 37-spline hub for a 1.6-inch diameter camshaft, and a 6-inch arm span, it is manually adjusted to keep brake shoe-to-drum clearance within spec. Often used on Fruehauf trailers with Propar axles, this part directly cross-references to Haldex KN44041 and many other OEM/aftermarket numbers.
Part Number: ACF6404-1
SLACK ADJ 37 SPL 6
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
