Its a interesting design this.
For one it still used precombustion chambers (This engine was made in the 1960s and 1970s) when most large Diesel engines had long adopted direct injection, giving it the characteristic old-school clatter and thus the “Clatterpillar” nickname. On the other hand the engine had a DOHC cylinder head which is rather rare even today. It was also not a completely new engine, the basic design is derived from the earlier D343 industrial engine. Power outputs of up to 425hp on the other hand are impressive even by modern standards.