The guide describes how to adjust an auto slack brake adjuster. Secure the vehicle, then remove and measure the push rod’s position. Adjust the slack adjuster bolt and re-insert the push rod. Test and measure to ensure brake components are within specified limits.
The front and rear brake air chambers are steel housings linked to an air compressor and feature push rods and S-cams. Pressing the brake pedal pumps air into the chamber, activating the push rod and S-cam to stop the tires. Rear chambers are dual-systems that also function as parking brakes, containing a powerful spring that can be manually activated. Both types of chambers use air pressure for effective braking, as traditional hydraulic systems are insufficient.