A seal is adapted to be received in an annular groove in a first member and is compressed against a groove bottom by a second member that defines a gap between the first and second members. The seal includes a reinforcement member and an elastomer body over-molded on the reinforcement member. The reinforcement member is disposed on an outboard side of the elastomer body and the elastomer body extends both above and below the reinforcement member. The compression of the seal causes the elastomer body to deform such that the reinforcement member provides a reinforcement substantially along the entire gap to prevent the elastomer body of the seal from being extruded through the gap.