Abstract: A powered jacking mechanism for semi-trailer landing gear is disclosed. The mechanism includes a coupling for attachment to an operating rod of a semi-tractor trailer landing gear jack. The coupling includes an idler sleeve for retaining the manual jack handle with the trailer during powered operation of the jack. The coupling includes a modified drive socket for selective coupling with either a drive end of the manual jack handle and a drive bit coupled to a rotary drive unit. In preferred embodiments, the rotary drive unit is a cordless screwdriver.