A brake assembly for a mobile machine is disclosed. The brake assembly may have a brake housing, an output member rotatably disposed within the brake housing, and a disc stack disposed within a cavity of the brake housing. The disc stack may include a plurality of friction discs coupled to the output member and a plurality of separator plates interleaved with the plurality of friction discs and coupled to the brake housing. The brake assembly may also have a piston disposed within the cavity and configured to compress the disc stack, and an indicator received within a bore of the brake housing against the piston. The indicator may include a first feature configured to provide at least one of visual and tactile indication of wear of the disc stack, and a second feature configured to provide at least one of a visual and tactile indication of failure of the disc stack.