Ever since Dodge began building their own cars in 1914, the company also offered light truck models. Initially, these were largely based on the existing passenger cars, but eventually gained their own chassis and body designs as the market matured. During the 1930s and 1940s, light- and medium-duty models were offered at first, then a heavy-duty range was added. The very large, new Warren Truck Assembly plant was built in Michigan, just north of Detroit, and opened in 1938, producing Dodge trucks ever since.