The country's major automotive need during this period was for commercial vehicles, with the situation complicated by the fact that in the first few years there was a severe fuel shortage. Mitsubishi's B1 bus, introduced in 1946, could be run either on gasoline or alternative fuels. Its chassis was an ideal platform for fire engines and other special-purpose vehicles. The MB46, launched in 1947, was an electric bus. In 1950, Mitsubishi marketed the R1, Japan's first rear-engine bus.

In the truck field, Mitsubishi continued its role as pioneer: the T31 (1951) featured an original type of chassis, the follow-up T33 was Japan's first truck to be equipped with an air suspension system, and the T380 was the first tilt-cab truck built in Japan.