China Railways SL5

As speeds increased and trains got heavier with the introduction of steel passenger carriages, the Pashishi class became inadequate, and the Pashiko class was ordered as a replacement. It was the first locomotive designed by Nobutarō Yoshino (吉野信太郎), who had returned to Japan in 1927 after two and a half years of studying at the American Locomotive Company, and who went on to be involved in the design of most subsequent Mantetsu locomotives. To boost the performance, cylinder size was increased and the fire grate was made larger. The Pashiko class was the first Mantetsu locomotive to be equipped with a combustion chamber firebox, and the first passenger locomotive to be fitted with an automatic stoker. With the introduction of the Pashiko class, of which eleven were built by the Shahekou Works in 1927 and 1928, the travel time of the Dalian–Changchun "Hato" express train dropped from 12 hours 30 minutes in 1929 to 10 hours 30 minutes in 1933. In 1934 they were used for high-speed tests of the "Asia Express" between Dalian and Fengtian. Until the arrival of the streamlined Pashina class, these locomotives were the most emblematic of Mantetsu passenger service.