An impeller attach mechanism for a turbocharger including a stud extending from a central bore of a compressor impeller toward a turbine wheel, the stud having a first threaded region and a second threaded region; a shaft coupled to the turbine wheel and extending toward the compressor impeller, the shaft having a leading portion, the leading portion having a threaded interior configured to engage the second threaded region of the stud; and an insert having an internal portion and an external portion, the internal portion having a threaded external surface to engage the compressor impeller, the internal portion having a threaded internal surface to engage the first threaded region of the stud, the external portion configured to surround the leading portion of the shaft.