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STEMCO · Brakes & Wheel End
MK42106S
In stock · ships from Knoxville
The STEMCO Crewson MK42106S is an automatic slack adjuster for heavy-duty truck and trailer air brake systems.
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Fits 1.5-inch diameter, 28-spline camshafts with a 6-inch arm and straight clevis (5/8-18 UNF thread). Not vehicle-specific; verify spline size, arm length, and clevis type before ordering.
Part data verified against 5 catalog sources
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It automatically maintains proper clearance between the brake shoes and drum, ensuring consistent braking performance and eliminating the need for frequent manual adjustments. A patented Auto-Check™ indicator lets you quickly verify brake adjustment at a glance. The unit fits a 1.5-inch, 28-spline camshaft, has a 6-inch arm length, and a straight clevis with 5/8-18 threads. Replace it when the existing adjuster is worn, seized, or fails to hold adjustment, typically during a brake overhaul or when brake stroke is out of specification.
Part Number: MK42106S
AUTO SLACK ADJ.
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
