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Stemco · Brakes & Wheel End
MK42700S
In stock · ships from Knoxville
This is an automatic slack adjuster for heavy-duty truck and trailer air brake systems with S-cam brakes.
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Verified fitment for 2 applications
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All confirmed applications for this part number.
Other applications
Other applications
Fits 1.5-inch diameter, 28-spline camshafts common on many trailers. Also cross-referenced as Vanguard part BRK00016. The Auto-Check stroke indicator is calibrated for T-30 standard stroke chambers or T-16/T-24 long stroke chambers.
Part data verified against 4 catalog sources
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It automatically maintains the correct distance between the brake shoes and drum as the linings wear, so you don't have to manually adjust the brakes. The built-in Auto-Check indicator gives a quick visual reference of brake stroke, helping you catch problems during a pre-trip inspection. Replacing a worn or seized slack adjuster with this unit helps restore even braking and keeps your rig in compliance with DOT roadside inspection standards.
Part Number: MK42700S
AUTO SLACK ADJUSTER
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
