The GE Dash 8-40B (or B40-8) is a 4-axle diesel-electric locomotive built by GE Transportation Systems between 1988 and 1989. It is part of the GE Dash 8 Series of freight locomotives. A total of 151 examples of this locomotive were built for North American railroads. The GE Dash 8-40BW (B40-8W) is a variant fitted with a full-width cab. Another variant is the GE Dash 8-40BP, more commonly known as the Genesis series. The locomotives in the Genesis series are the P40DC, the P42DC, and the P32AC-DM.