Thomas Built Buses, Inc. (commonly designated Thomas) is an American bus manufacturer. Headquartered in High Point, North Carolina, the company is a subsidiary of Daimler Trucks North America (the parent company of Freightliner). While best known for its yellow school buses, Thomas also produces, activity buses/MFSAB (Multi-Function School Activity Buses), commercial buses, and bus bodies for aftermarket conversion.
International Harvester S-Series (bus chassis)
The International Harvester S-Series “Schoolmaster” is a Type C (conventional) bus chassis that was manufactured by International Harvester and then Navistar International from 1979 to 1989. In 1989, the S-Series was updated and renamed the International 3800. It was used primarily as a cowled chassis for both school bus and commercial bus applications; it also was the basis for the front and rear-engine stripped chassis that International uses for bus applications as well.
The 3800 is notable for being the first American school bus chassis to have an engine lineup consisting only of diesel engines.