An air maintenance tire and air pump assembly includes a sidewall and a tire cavity for maintaining pressure; an elongate tubular air passageway enclosed within a flexing region of the sidewall, air passageway, the air passageway operably closing segment by segment in reaction to induced forces from the tire flexing region as the flexing region of the tire wall rotates adjacent a rolling tire footprint, the elongate air passageway having at least one check valve device seated within the axial air passageway; and a relief valve assembly comprising a chamber body, a valve, a piston, and a silicone ring, the valve having a valve body and a valve head, the valve head, deforming to release over-pressurized air from the tire cavity to atmosphere.