At the time it was considered unusual to say the least to match a 4-ton truck engine with a compact truck chassis, but in reality these were the only materials that Toyota had to work with. It turned out to be a successful combination. An ample sized body useful for transporting materials driven by an engine with power to spare, this model met multiple needs in the market for a compact 4x4 vehicle at a high level. Moreover, the fact that it was not adopted for use by the Police Defense Forces actually turned out to be a major stimulus for the development of an export strategy, with considerably more freedom in design and development, and became a key factor in Toyota's successful overseas launch.
However, in 1953 Toyota did receive a procurement order from the National Police Agency, and the plant in charge of production was the Arakawa Bankin Kogyo KK (now called ARACO Corporation). With regular orders for large-scale production, the factory literally worked around the clock to meet demand. The process worked like this: first the parts for the chassis would be shipped from Toyota Motor Corporation for assembly at the Toyoda Automatic Loom Works, Ltd., then transported to the Arakawa Bankin Kogyo KK, where the body was painted. The completed vehicles would then be shipped overland back to the Toyoda Automatic Loom Works, Ltd., where they would be inspected by officials from the National Police Agency, whose demands could be met by a team of about 20 people who could do finishing work and make adjustments.

The Toyota BJ-type was a multi-purpose compact truck based SB-type truck, and went through a series of body shape design changes over time. The original short body hooded cargo and passenger carrier type was converted to a metal top type, and a closed type passenger model was also released. For the cargo carrying version the rear was extended by 500mm and converted to a pickup truck, and there was also a truck with a separate unit cabin and truck bed. There were many variations according to where the spare tire was located, not only on the rear gate, but even on the front fender or below the truck bed.

Because the body has a rather squeezed nose design, the diameter of the steering wheel covers about half of the instrument panel. For that reason the driver's seat feels rather cramped, and when you carry a passenger it makes it a bit difficult to steer. In the later 20-series models the steering wheel was moved further to the outside.