The Class D60 (D60形) is a Japanese 2-8-4 Berkshire wheel arrangement steam locomotive type created by rebuilding an earlier class to suit post-war requirements. 78 of the successful pre-war 380-strong Class D50 2-8-2 Mikado locomotives. The D60s were rebuilt between 1951 and 1956 at the JNR Hamamatsu (Nagoya) Region, Nagano, (Nagoya) Region, and Tsuchizaki, (Sendai) Region workshops. As with the rebuilding of Class C59 to Class C60 locomotives, an additional trailing axle was included to reduce the heavy axle load of the D50 and allow more widespread use. The cylinder diameter was reduced from 570 mm on the D50s to 550 mm to minimize wheel spin.