Union Pacific’s dedicated Mechanical team has responsibility for inspecting, repairing or rebuilding more than 4,500 active locomotives and 300,000 rail cars traversing our network. Jenks is UP's premiere locomotive and component overhaul facility, touting 560 tons of crane capacity. The shop building is named for Downing B. Jenks, a Yale graduate who became the youngest railroad president in the United States when he took over the Rock Island Railroad before moving to the Missouri Pacific in 19