In May 1950, while the dispute was ongoing, the Shibaura and Kamata Plants in Tokyo were declared as financially independent and began preparations for closure.

The Shibaura Plant had been opened in May 1936 as the Shibaura Laboratory of the Automotive Department of Toyoda Automatic Loom Works, but 90 percent of the facilities were destroyed by fire in the Tokyo air raids of March 1945.1 Following its post-war restoration, it undertook vehicle refurbishment and repair. In June 1950, when the Shibaura Plant was closed down, its staff was transferred to two newly established companies: Tokyo Shibaura Automobile Works Co., Ltd. (President: Shinji Hasegawa, former general manager of the Shibaura Plant), and Japan Vehicle Body Co., Ltd. (Representative: Yasuo Naito2) The two companies leased the facilities of the former Shibaura Plant and carried on vehicle refurbishment, repair, mounting of vehicle bodies, and other operations.

However, both companies were dissolved in 1953 due to lack of business and their facilities and staff were taken over by Toyopet Seibi Co., Ltd., established in June 1954, which was renamed Toyopet Service Center Co., Ltd. in 1964 and Toyota Technocraft Co., Ltd. in 1990. Today, its operations include vehicle upgrading and repair, mounting for and modification of special vehicles, and commissioned vehicle development, prototype production, and modification.

Following the war damage to the Shibaura Plant, the Kamata Plant was leased to replace it after the war from Nippon Nainenki Seizo, a company whose president was the former Toyota Motor Co., Ltd. director Jinkichi Terada3 (during whose presidential term Kiichiro Toyoda was also a company director). In February 1947, the Kamata Plant began modification and refurbishment of decommissioned vehicles from the occupying forces (GMC weapon transport vehicles).

(during whose presidential term Kiichiro Toyoda was also a company director). In February 1947, the Kamata Plant began modification and refurbishment of decommissioned vehicles from the occupying forces (GMC weapon transport vehicles). With the aim of business conversion, the plant tried its hand at prototype production of compact truck bodies and other operations, but these experiments were interrupted by the recession brought on by the Dodge Line, and the plant was forced to close as part of the Toyota Motor Co., Ltd. reconstruction plan.4

The Kamata Plant facilities were returned to Nippon Nainenki Seizo and its employees had to be reassigned to different work. Central Motor Co., Ltd., one of the new businesses which resulted, launched into the vehicle body mounting business, and later became responsible for body manufacturing and assembly for new Toyota vehicles.5