Product Details: Update your truck with the ideal amount of tension in the brake linkage, with the Meritor 1.5" Cam / 28-Spline / 5.5" Automatic Slack Adjuster that ensures you're Ready for the Road Ahead™. By utilizing a tension-based design, this replacement component is able to check the amount of slack between the brake shoe and the brake drum, and automatically adjust the distance as needed to reduce overall wear. Constructed with a compensating mechanism that alters the position of the pushrod as the brakes wear down.