Bonded piston seal for power steering

A seal assembly which acts as a piston in a vehicle power steering unit. The seal includes a casing and an elastomeric seal body and is affixed to a movable rack at two attachment points. One point is the tail portion of an axial flange swaged into a groove in the rack, and a second part of the same axial flange has a groove for retaining a locking ring in a second groove in the rack. The rack moves within a housing having a first bore, a counterbore, and an enlarged bore. The seal comprises two oppositely facing lips and a lip body bonded to a radial flange of the seal assembly and engaging the enlarged bore which divides the space into two pressurizable fluid receiving cavities. An auxiliary seal is seated in the counterbore and seals the first bore. The seal assembly has a nose portion which engages the auxiliary seal to fully seat it in the counterbore. The nose portion, in one case, is a separate axially extending plastic piece that seats in a groove in the seal body. In another embodiment, the nose portion is a separate metal ring, and in still other embodiments, the nose portion is made up of extensions of the seal casing.