A full crew-cab dually by trade ... More precisely, the engine bay of the C30 is where a 5.9-liter, six-cylinder Cummins engine was lowered and tied to a six-speed automatic transmission.

Durant Headquarters Detroit, Michigan Current CEO Mary Barra The C30 started life as a regular pickup truck and now spends its time as a full crew-cab dually pickup with a Cummins 5.9L diesel.