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Pro-Par · Brakes & Wheel End
PROSA56074
In stock · ships from Knoxville
This is an automatic slack adjuster for the air brake system on heavy-duty trucks and trailers.
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 automatically maintains the proper clearance between the brake shoes and drum, ensuring even braking performance. Replacement is typically necessary when the adjuster stops self-adjusting, becomes seized, or shows excessive wear at the splines or clevis. This specific model has a 1.5-inch, 28-spline bore, a 6-inch straight arm, and a Meritor-compatible mounting style for direct installation on many trailer and drive axle applications.
Part Number: PROSA56074
AUTO SLACK, 28SP, 1-1/2, 6
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
