BRAKE SYSTEM Drum Brakes Automatic Slack Adjusters Have brake drum linings and disc brake pads inspected by a qualified mechanic for wear at regular intervals according to the maintenance schedule. In severe service or off-highway applications inspect the linings more frequently. Periodically check the Brake Chamber Stroke. Replace the slack adjuster if proper stroke cannot be maintained. Operational checks of automatic slack adjusters Measure brake chamber stroke with the spring brake released and the air pressure no less than 100 psi (690 kPa). Brake Chamber Stroke is the difference between the applied and the retracted position of the air chamber pushrod.
5 A correctly installed and functioning auto slack adjuster will produce the following strokes: Brake Chamber Stroke (03/17) Y53-6077-1B1 5-69 Chamber Type Stroke 36 (rear brakes) 1-1/2" - 2-1/4" (38 - 57 mm) 30 (rear brakes) 1-1/2" - 2" (38 - 51 mm) 16, 20 and 24 (front brakes) 1" - 1-3/4" (25.4 - 44.4 mm)