American Railcar Industries (ARI) was founded in 1994 through the acquisition of the railcar component manufacturing and maintenance units of American Car & Foundry (ACF). In 2005, ARI began manufacturing 5200 cubic foot, 3-bay hopper cars for Union Pacific under their CMO (former CNW) reporting marks since UP had more cars than available numbers for this car order. The design followed close ties to former ACF hopper car products. UP under the Chicago Heights Terminal Transfer RR (CHTT) placed another order in 2006, as did CIT Group for ownership and for leasing operations. Kansas City Southern Railway placed a substantial order of these cars in 2007, choosing to bring back the Southern Belle paint scheme, creating a stunning black/red/yellow/gray combination of colors. UP again placed another car order in 2014, choosing to bring these cars out with UP reporting marks, having divested some older cars from the fleet. These cars are very recognizable by such spotting features as the triple-ribbed top sill on the main body, two vertical end supports toward the middle of the end panels, and a narrow drop sill on the bottom ends of the car which provide a distinct difference from other cars similar in style. Some of the car owners had the cars fitted with pneumatic impactors on one end to help flow products out of the car. Four different roof loading hatch variants were used on these cars. In 2019, ARI was acquired from ITE Management by The Greenbrier Companies.