Baaed on the last two decades experiences of diesel engine 6120 production, the 12 L engine X6130 series were designed and developed. High percentage of commonality makes it possible to utilize 83% of the existing special machines. Direct injection combustion system, construction of higher rigidity and alloyed spheroidal iron crankshaft characterize the main features. Nitriding of the crankshaft enables the material suitable even for TC engines. TCA version is also under development. The whole series will cover a power range from 154 to 240 kW.