与总计360台956系列柴油机使用于牵引的同时,发展了20缸机使功率范围扩展到5000马力(UIC)。增压空气的直接空气冷却带来了重要的重量和尺寸方面的经济性,减少了保养工作,并且通过机油的空气冷却也能够获得同样的利益。当趋向于较高的速度同时较少地强调粘着重量时,借助956系列的良好特性,用2台柴油机按C_0-C_0轴式,可以满足在23吨轴重以内组成8000马力的机车。 Together with a total of 360 956 series diesel engines for traction, a 20-cylinder engine was developed to extend the power range to 5,000 horsepower (UIC). Direct air cooling of the pressurized air brings significant weight and size economy, reduces maintenance work, and also benefits from air cooling through the oil. When the trend toward higher speed with less emphasis on adhesion weight, with the 956 series of good features, with 2 diesel engine according to C_0-C_0 axis type, to meet the composition of 23,000 tons of axle weight 8000 horsepower within the locomotive.