A Legendary History

Isuzu marks the 78th anniversary of its long and prosperous involvement with diesel engines in 2012. Isuzu's history has coincided with the development of diesel engines in Japan.

Origins of Isuzu Diesel
The DA6, completed in 1936, was not only the first Isuzu diesel engine but also Japan's first air-cooled diesel.
After the German engineer Rudolf Diesel developed the world's first diesel engine in 1893, decades passed until the birth of Japan's first practical automotive diesel engine.
While Japan's first diesel engine was developed by the Navy in 1907, the model was not for practical use but for research use. However, many private companies continued their efforts to develop diesel engines for various industries including the automobile industry.
Automobile Industries Co., Ltd., an Isuzu predecessor, established a diesel research committee in 1934, as part of the operational policies of then President Tomonosuke Kano. Just two years later in 1936, the company manufactured Japan's first air-cooled diesel engine, which marked a breakthrough in the history of diesel engine development.
This engine model surpassed competitors when vehicles for both civilian and military use equipped with it soon. Automobile Industries was merged with two other companies into Tokyo Automobile Industries Co., Ltd. in 1937.
The Japanese government designated Tokyo Automobile Industries in 1941 as the only company that was permitted to manufacture diesel-powered vehicles. Thus, the company, which was renamed Isuzu Motors Limited in 1949, has established strong foothold in the industry to lead the diesel engine technology.

Postwar Era
In response to the fast growing demand after the World War II for restoring vehicle production, Isuzu Motors developed the DA80 diesel-Japan's first V8 engine-in 1950.
In addition, Isuzu developed a pre-combustion chamber, which had been improved through wartime to the postwar era as the industry's standard indirect-injection combustion chamber.
Isuzu also developed a direct-injection combustion chamber in which an advanced configuration was incorporated. The model attracted the industry's attention for its high performance.

Japan still suffered a shortage of fuel early in the decade. However, the launch of Isuzu's bonnet-type truck in 1959 led to explosive sales. With the excellent fuel economy of its DA640 diesel, it boasted rugged performance on bumpy roads and extra durability even if the truck was heavily over-loaded.
Isuzu developed Japan's first diesel engine for passenger cars in 1961. The DL201 model was presented with the 1961 Technological Award by the Japan Society of Mechanical Engineers.
The DL200 model, which was mounted in 1964 on the Elf, Japan's first cab-over light-duty truck, has gained great popularity in the market thanks to its excellence in economy and durability.
TX61 dump truck
The diesel-powered TX61 dump truck worked throughout Japan during postwar era for recovery from wartime damages.
Japan entered the age of high-speed transportation in the decade by enhancing transportation infrastructure, backed by a fast growing economy. In the latter half of the period, the U.S. dollar crisis in 1971 and the first oil crisis in 1973 forced automakers to pay attention to energy-saving vehicles, competing with each other in developing turbo-charged engines and intercooled engines. Air pollution and noise also became critical issues for the automobile industry.
To cope with the trend, Isuzu adopted in 1973 its newly-developed low-emission, light-weight and high output PA model in the V Series lineup to ten-ton payload trucks and tractors.

The second oil crisis in 1979 resulted in further implementation of energy-saving measures among industries in Japan. This helped recovery of Japan's sluggish economy. The automobile industry saw an increasing customers' need for vehicles which featured, in addition to enhanced safety, low pollution, high output and good fuel economy.
In response to this need, Isuzu put on sale in 1981 ten-ton payload trucks equipped with high-torque, fuel-saving turbo-charged 8PB1-T and 6RA1-T engines. In 1983, the company released a new heavy-duty truck series in Japan, named as the 810 Series, after carrying out the first full-scale changes in 15 years. Improved features of the new series included the introduction of advanced diesels such as electronically controlled 6RA1-TC turbo-charged model, which incorporated intercooled design, and the V-type PC Series engines, which boasted enhanced displacement.
In small diesels, Isuzu promoted the use of fuel-efficient diesels in passenger cars through the release of the diesel-powered Florian and Gemini in 1977 and 1979, respectively.
Isuzu led the industry in the field of direct-injection diesel engines for light-duty trucks. In 1981, the company introduced direct-injection design, which features both high output and low fuel consumption, to all diesels mounted on two-ton payload trucks. In addition, It was Isuzu that developed world's first full-scale electronically controlled diesel for both light- and heavy-duty trucks.
Isuzu also led the industry in developing ceramics for diesels. Isuzu developed the Ultra Quick on Start (QOS) system in 1981, which eliminated preheating time during start-up for the first time in the world. The system, which incorporated a newly-developed ceramic glow plug with high heat-resistance and electronic control, became indispensable for diesels, especially in passenger cars.

Current operation
Today, Isuzu has global diesel engine production network, sparing no efforts to develop low impact clean diesel engines in response to a growing market need. Isuzu diesels are highly accepted and praised in the global market and are chosen by excellent automotive companies in Europe and USA. They count on Isuzu diesels for its superior performance and excellent fuel economy, which is a clear endorsement of the overall high quality and excellent environmental engineering of Isuzu diesels.