Your cart is empty
Browse our catalog to find the parts you need.
These images are illustrative and may not match the product exactly. Always verify by part number — or confirm instantly with the assistant using a photo or VIN.
Automann · Brakes & Wheel End
138.2810
In stock · ships from Knoxville
This is an automatic slack adjuster for heavy-duty truck and trailer air brake S-cam 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, automatically maintaining proper brake shoe-to-drum clearance to ensure consistent braking performance. This unit follows the Gunite style design, featuring a 1.5-inch diameter bore with 28 splines and a 5.5-inch arm length (center-to-center). Replace this component when the internal adjustment mechanism wears or fails, causing excessive brake slack that can lead to reduced braking power and uneven wear.
Part Number: 138.2810
5.5IN GUNITE SLACK ADJUSTER
Unit: ea
Vendor: Automann
Dealer: KP Services Crossville
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
