Vs  How come there are no v engines for class  trucks in North America   There were V Detroits and V Silver Detroits that were wellrenowned motors for Class  trucks  I believe that currently the educated thought is that inline cylinder engines can fit into a tighter space profile with accessories such as air compressors allowing truck hoods to be sized smaller     The reason might be that the inline cylinder engines are  obviously  of a much simpler configuration since there is only one bank of cylinders verses two banks of a V design  Also there are significantly fewer highprecision parts in a cylinder engine verses an cylinder engine eg pistons connecting rods valves injectors  Routing of intake air and exhaust gas is simpler in an inline engine verses a V type engine  Thus an inline cylinder is easier and less expensive to design manufacture and maintain than a Vtype cylinder  Additionally I believe the inline  design is more efficient than the V because there is less heat loss  Fourcycle V diesel truck engines were manufactured for class  trucks by both Caterpillar eg the  and Cummins eg the  up until the early to mid s  Detroit Diesel stopped making cycle engines for motor vehicles because those engines were incapable of meeting the more stringent exhaust gas emission requirementsPreceding unsigned comment added by     August