Cadillac Commercial Chassis

Coinciding with a change in design regulations and the downsizing of Cadillac sedans, the Commercial Chassis was phased out as a distinct product line.

While fitted with all road controls and front body trim (and air conditioning, if specified), all bodywork from the dashboard rearward was completed by coachbuilders using the chassis as a basis for a completed vehicle; to aid body fabrication, front door shells and rear quarter panels were shipped to the coachbuilders (separate from the chassis).

Before World War II, the Commercial Chassis used the longest wheelbase of any GM sedan-based vehicle, ranging up to 165 inches in 1940.

The professional car industry underwent a period of struggle, as multiple firms either closed their doors or were reorganized (such as Superior, Miller-Meteor and Hess & Eisenhardt).

On an official basis, Cadillac has produced "incomplete"-bodied versions of several of its unibody-chassis product lines, including the DeVille, DTS, XTS, and CT6.