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 postwar requirements. 78 of the 380 successful, powerful prewar Class D50 2-8-2 Mikado locomotives were rebuilt and redesigned as D60s between 1951 and 1956 by Hideo Shima at the JNR Hamamatsu (Nagoya) Region, Nagano, (Nagoya) Region, and Tsuchizaki, (Sendai) Region workshops. As with the rebuilding of Class D51 to Class D61 and Class D52 to Class D62 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, and they were built to replace the older Class 9600s in 1951. The D60s have a top speed of 80 km/h.