In 1926, the Tokyo-based DAT Motors merged with the Osaka-based Jitsuyo Jidosha Co., Ltd (Jitsuyō Jidōsha Seizō Kabushiki-Gaisha) a.k.a. Jitsuyo Jidosha Seizo (established 1919 as a Kubotasubsidiary) to become DAT Jidosha Seizo Co., Ltd Automobile Manufacturing Co., Ltd.  DAT Jidōsha Seizō Kabushiki-Gaisha) in Osaka until 1932. From 1923 to 1925, the company produced light cars and trucks under the name of Lila.[15] In 1929, DAT Automobile Manufacturing Inc. merged with a separated part of the manufacturing business of IHI Corporation to become Automobile Industries Co., Ltd. [clarification needed] In 1931, DAT came out with a new smaller car, called the Datsun Type 11, the first "Datson", meaning "Son of DAT". Later in 1933, after Nissan Group zaibatsu took control of DAT Motors, the last syllable of Datson was changed to "sun", because "son" also means "loss" in Japanese, hence the name "Datsun" , Dattosan).

In 1933, the company name was Nipponized to Jidosha-Seizo Co., Ltd. (Jidōsha Seizō Kabushiki-Gaisha, "Automobile Manufacturing Share Company") and was moved to Yokohama.