UD Trucks

UD Trucks Corporation (UDトラックス株式会社, UD Torakkusu Kabushikigaisha) is a Japanese company whose principal business is the manufacturing and sales of diesel trucks, buses, bus chassis and special-purpose vehicles. Its headquarters are located in Ageo, Saitama, Japan. The company is a wholly owned subsidiary of Isuzu since 2021. Until 2010, the company was known as Nissan Diesel.

The UD name was originally used for the company's Uniflow Diesel Engine (a two-stroke diesel engine), developed in 1955, but is now marketed as meaning "Ultimate Dependability".

In December 1935, Nihon Diesel Industries, Ltd, in Kawaguchi, Japan on the outskirts of Tokyo was established under the leadership of Kenzo Adachi, where he purchased diesel engine schematics from a Krupp-Junkers patent. The company started production of KD-series 2-cycle diesel engines after entering into partnership and technology exchange with Friedrich Krupp AG. In November 1939, to test the durability of the LD1 truck, the company went on a 3,000 km (1,864.1 mi) test drive across Japan. The drive went to the villages of Hakone, Osaka, Kyoto, Gero, Ikaho, Niigata and Aizu before returning to Kawaguchi. The route was on very primitive mountain roads and very rural conditions. The truck returned 13 days later on November 20 without incurring any failure, and soon the trucks’ reliability became known. In 1940 production of 4.5-ton-payload TT6 series trucks started, and in 1942 the company was now known as Kanega-Fuchi Diesel Co., Ltd. In development of 7.5-ton-payload TN93 series trucks, featuring the largest payload capacity in the Japanese market, and the nation's first monocoque-type BR3 series buses with rear-mounted engines. In 1946 the company name changed to Minsei Industries, Ltd. In 1949 development of 7.5-ton-payload TN93 series trucks started.

In 1950 Minsei Diesel Industries, Ltd. was spun off from Minsei Industries; and the company was on the way to becoming a comprehensive transport equipment manufacturer. In 1955 the UD name was born, when Minsei Diesel Industries introduced a range uniflow-scavenging 2-cycle diesel engine. Of course, the UD stood for "Uniflow Diesel", named after the engine they had invented for use in their trucks. The production of various trucks and buses with 81 kW (110 PS) UD3, 110 kW (150 PS) UD4 and 169 kW (230 PS) UD6 engines began. In 1957 the development of Japan's first RFA series air-suspension buses and 10-ton-payload 6TW10 series trucks called "Jumbo" in overseas markets began.

In 1960, Nissan Motor Co., Ltd. acquired Minsei Diesel, and was renamed Nissan Diesel Motor Co., Ltd. Forward-control trucks and truck tractors were also introduced. In 1963, there was the initial production of compact 4-cycle 40 kW (55PS) SD20 and 44 kW (60PS) SD22 diesel engines. 70 to 80-ton crane-carrier truck series were also introduced to the line-up. 1969 saw the introduction of 4-cycle 136 kW (185PS) PD6 and 99 kW (135 PS) ND6 diesel engines for heavy-duty vehicles. Diesel products were sold in Japan at a separate dealership sales channel called Nissan Diesel. In 1969, the 780-series replaced the 680-series bonneted truck.

In 1971 the heavy Nissan Diesel C-series arrived, being replaced by the second generation in 1979. 1972 saw the marketing of V-type 206 kW (280 PS) RE8/RF8 and 257 kW (350 PS) RE10 diesel engines. In 1973, light-duty trucks were produced for the Nissan Motor Company.

In 1982 there was the introduction of new forward-control cab for the CWA52/45 series trucks (sold as the Nissan Diesel Resona in Japan), CKA-T series truck tractors and ultra-modern U(A)21, U(A)31, RA51 series buses. As of 1985 the company had a wide range of light-, medium- and heavy-duty trucks, as well as buses and special-purpose vehicles such as crane carriers. In 1989 there was an agreement with IVECO of Italy to jointly develop low-pollution diesel engines.

In 1992 Nissan Diesel Philippines Corp. started manufacturing deluxe coaches in cooperation with Jonckheere Bus & Coach NV/SA of Belgium. In 1995 Nissan Diesel produced its two millionth vehicles since commencing production in May 1950. 1996 brought about the establishment of PT Astra Nissan Diesel Indonesia, a joint venture company with Marubeni Corporation and Astra International, and the Dongfeng Nissan Diesel Motor Co., Ltd, a joint venture company with Sumitomo Corporation and Dongfeng Motor Corporation.