Abstract: This invention relates to an indicating apparatus to determine the amount of wear that has occurred in the friction material of a brake assembly or other friction coupling. The apparatus utilizes a pin member that is positioned in a sealed bore in the housing of the friction coupling. A first end portion of the pin member is positioned for contact and movement of an actuating piston when the piston is in an engaged position. The distance between the a second end portion of the pin member, housed within the bore, and an outer surface of the housing may be determined by a depth gage. Measurements may be taken to determine movement of the pin member within the bore and thereby establish the amount of wear of the friction material in the friction.