Slack adjusters are the linkage between the operating rod in the brake chamber and the S-cam (drum brakes) or power screw (disc brakes) in an air brake system.
slack adjusters are part of the brakes. they are ocated on the axle next to each wheel. they are used to adjust the brakes,or to take the slack out on the lickages so as the brakes do not have...
Why? ASA's are an improvement over manuals, and eliminates periodic adjustments. Legally, if it came with ASA, you must keep them on and maintain them. Read your CMV book, if you are in this...