Abstract: An automatic slack adjuster operating to effect reduction of slack present in a vehicle brake system upon brake release incorporates a member cooperating with a slack adjusting rotor to determine a reference position for the rotor and to return the rotor to such reference position at the completion of each brake operational cycle.

Abstract: A gage for use in mounting a slack adjuster having one end having an opening adapted to removably couple the slack adjuster to a brake control shaft and an opposite end having an opening adapted to removably receive a bearing pin for rotatably coupling the slack adjuster to a clevis adjustably mounted on a brake actuating push rod, wherein the gage includes an elongated body having first and second ends, the first end having a first bearing surface adapted to engage with an outer surface of the control shaft, and the second end having a second bearing surface adapted for engagement with the bearing pin and an indicator for indicating when the position of the clevis lengthwise of the push rod provides a given angle between an axis extending lengthwise of the push rod and a line drawn through centers of the control shaft and the bearing pin.