Slack adjuster air brakes setting

If you set the slack adjuster to you air brakes regularly you will have a much safer vehicle.

Is it manual or automatic?

Consult the owner’s manual to see this information. The automatic slack adjusters should be checked by a specialist.

Always check and adjust your manual adjusters at every pre-trip inspection


Verify if the slack adjuster needs resetting. See if the push rod moves more than ¾ inch when you pull it out. If so adjustment is needed.


Turn the bolt in the direction that the push rod moves inward. When you feel resistance back up ¼ to ½ a turn and then check again to see if the push rod comes out less then ¾ inch.



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