Abstract: A radial seal and facial excluder seal are mounted on separate rings but installed in combination so that the excluder seal always maintains sealing engagement with its intended counterface notwithstanding wide axial assembly tolerances between the shaft and bore on which the seals are mounted, the excluder seal also serving to prevent contamination from coming into contact with the radial seal, and the ring on which the excluder seal is mounted serves as a guide for installation of the shaft past the radial seal in such a way as to reduce occurrence of damage to the radial seal as a result of sharp splines or other imperfections on the shaft.