Detroit Diesel is a manufacturer.
Detroit Diesel Corporation ( DDC ) is an American diesel engine manufacturer headquartered in Detroit , Michigan , United States and a subsidiary of Daimler Trucks North America , itself a wholly owned subsidiary of the German Daimler AG . The company manufactures heavy-duty engines and chassis components for the on-highway and vocational commercial truck markets . Detroit Diesel 's product line includes engines , axles , transmissions , and Virtual Technician .