CADILLAC by SUPERIOR COACH CORPORATION

In 1940 the company changed its name again, to Superior Coach Company. School bus bodies were built primarily on Chevrolet/GMC, Dodge, Ford, and International Harvester truck chassis. In 1951 the Lima facility was expanded and a new facility in Kosciusko, Mississippi was opened.

In 1969 Superior was acquired by the Sheller-Globe Corporation, an industrial conglomerate and auto parts maker based in Toledo, Ohio.

The 1977 model year saw a major downsizing in the Cadillac automobile chassis used for the professional car business. In addition to being smaller, Cadillac's commercial chassis was significantly more expensive. Superior and other ambulance and funeral car manufacturers had to design new bodies and retool their factories, resulting in much higher consumer costs. The ambulance sector switched to larger van-based vehicles or and truck chassis. 1977 also brought new Federal Motor Vehicle Safety Standards for school buses built after 1 April, which increased both costs and engineering challenges.^{[citation needed]} At the same time, a downturn in North American school bus purchase volumes began as the children of the Baby Boom generation completed their elementary and secondary educations.