Dual Locomotive Dual Mode. On the night of Friday, March 14, 2025, MTA Metro-North Railroad/Siemens SC42-DM MNCW 301 tested on the Hudson Line with MNCW 229 (New Haven, P32AC-DM). This was a test of both locomotives operating together in electric mode. The SC42-DM locomotive is one of 33 on order to start to replace the railroad's General Electric P32s. Though similar to the all diesel design of the SC-44 and ALC-42, these locomotives also had to go to the testing center in Pueblo, Colorado for full evaluation before delivery to Metro-North. The locomotives are much quieter than their predecessors, and also significantly more fuel efficient while providing more power. On this night the train operated both in electric (third rail) mode up to around Croton Harmon, and diesel mode from there to Poughkeepsie. While the (present) GE P32AC-DM fleet changes from electric to diesel mode around the Harlem-125 Street Station, MNR has stated that this locomotive is designed to operate on third rail to the Croton Harmon area, where electrification ends.