An auto slack adjuster is a mechanical component used in air-braked vehicles to automatically adjust the brakes

An auto slack adjuster is a mechanical component used in air-braked vehicles to automatically adjust the brakes. It is designed to maintain the proper brake drum clearance, also known as "slack," to ensure the brakes remain functional and effective. The auto slack adjuster works in conjunction with the air brake chamber, which is attached to the brake drum, and the push rod, which is connected to the brake pedal. When the brake pedal is depressed, air pressure is sent to the air brake chamber, which pushes the push rod and activates the brakes. The auto slack adjuster helps to ensure that the proper amount of slack is maintained, even as the brake linings wear down, so that the brakes remain effective.
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