A turbocharger assembly comprising: a housing that comprises a bore; a turbine wheel; a bearing disposed in the bore of the housing; a compressor wheel that comprises a base surface, a nose surface, a z-plane disposed between the base surface and the nose surface and a bore extending from the base surface to the nose surface; a steel shaft is rotatably supported by the bearing in the bore of the housing wherein the steel shaft comprises a first pilot surface (P A) disposed in the bore of the compressor wheel at a position between the z-plane and the nose surface and a second pilot surface (P B) disposed in the bore of the compressor wheel at a position between the z-plane and the base surface, and a recessed portion disposed between the first pilot surface (P A) and the second pilot surface (P B); a thrust collar is disposed about the shaft between the bearing and the base surface of the compressor wheel, wherein the thrust collar comprises a compressor wheel facing surface, a bearing facing surface and a bore extending therebetween a nut is adjustably disposed on the steel shaft adjacent to the nose surface of the compressor wheel wherein adjustment of the nut tensions the steel shaft to apply a compressive load between the base surface and the nose surface of the compressor wheel, characterized in that the housing comprises a lubricant passage; the bearing comprises an opening to receive lubricant via the lubricant passage of the housing; the steel shaft comprises an outer surface that extends to a shoulder; another recessed portion is disposed between the second pilot surface (P B) and the shoulder, the thrust collar comprises an interior surface that seats the shoulder of the shaft by the interior surface and the shoulder contacting and the nut is adjusted with respect to the steel shaft to cause the shoulder of the steel shaft to apply force to the interior surface of the thrust collar, which, in turn, applies force to the base surface of the compressor wheel. a housing that comprises a bore; a turbine wheel; a bearing disposed in the bore of the housing; a compressor wheel that comprises a base surface, a nose surface, a z-plane disposed between the base surface and the nose surface and a bore extending from the base surface to the nose surface; a steel shaft is rotatably supported by the bearing in the bore of the housing wherein the steel shaft comprises a first pilot surface (P A) disposed in the bore of the compressor wheel at a position between the z-plane and the nose surface and a second pilot surface (P B) disposed in the bore of the compressor wheel at a position between the z-plane and the base surface, and a recessed portion disposed between the first pilot surface (P A) and the second pilot surface (P B); a first pilot surface (P A) disposed in the bore of the compressor wheel at a position between the z-plane and the nose surface and a second pilot surface (P B) disposed in the bore of the compressor wheel at a position between the z-plane and the base surface, and a recessed portion disposed between the first pilot surface (P A) and the second pilot surface (P B); a thrust collar is disposed about the shaft between the bearing and the base surface of the compressor wheel, wherein the thrust collar comprises a compressor wheel facing surface, a bearing facing surface and a bore extending therebetween a nut is adjustably disposed on the steel shaft adjacent to the nose surface of the compressor wheel wherein adjustment of the nut tensions the steel shaft to apply a compressive load between the base surface and the nose surface of the compressor wheel, characterized in that the housing comprises a lubricant passage; the bearing comprises an opening to receive lubricant via the lubricant passage of the housing; the steel shaft comprises an outer surface that extends to a shoulder; another recessed portion is disposed between the second pilot surface (P B) and the shoulder, the thrust collar comprises an interior surface that seats the shoulder of the shaft by the interior surface and the shoulder contacting and the nut is adjusted with respect to the steel shaft to cause the shoulder of the steel shaft to apply force to the interior surface of the thrust collar, which, in turn, applies force to the base surface of the compressor wheel.