THE LEGEND
Plans for the DT466 soon turned to the truck market and after a $500,000 tooling investment, it became an option for the Fleetstar, starting with January 1975 production. Later in the year, it became available in the Cargostar (COE) and Paystar. The DT466 was added to the Loadstar options list in the summer of 1976 as a premium upgrade over the naturally aspirated D150, D170 and D190 9.0L V8 diesels. The DT466 was more powerful, economical and reliable than the big V8 diesels and it could be overhauled in chassis.
The medium-duty market had been evolving towards diesels but the “just-right” engine had not yet been offered to make much of a stir. International had been offering a range of in house diesels over the years, like the D301, D358, DV462 and DV550 (later known as the 9.0L after some updates). Others came from outside, including Perkins, Cat, Cummins and Detroit Diesel engines. The idea of offering a premium wetsleeved turbo-diesel in a medium duty line that could be overhauled in-chassis like a heavy-duty truck was a new one and IH hit paydirt with it. The DT466 soon became the engine to beat in the medium-duty arena.
Going back to tractors, the 414 and 436 found immediate homes in the International tractor lines. The D414 debuted in the 1971 966 tractor. The DT414 debuted in the 1066, while the DT436 appeared in the 1466 and the 4166 four-wheel drive. The DT466 first appeared in the 1973 4366 four-wheel drive tractor, a co-development of IH and Steiger. All three of these engines had a history of stellar service in the IH tractor lines, even a little past when the ag side of IH was sold off and became Case IH. International Harvester was broken up into its component parts, with the truck and engine sections becoming Navistar International.
The DT466 had a large number of upgrades before it evolved completely away from mechanical injection in 1997. There were so many designations and power ratings that we’d need half the magazine to cover them all, so we’ll stick to the most common. The original DT466 iteration was built in 1977 and had a AMBAC Model 100 rotary pump. The two common ratings were 185 and 210 hp in trucks. When the DT466B appeared in 1977, the earlier engine became the DT466A by default.
The DT466B emerged with some internal changes. One of them was a revised ring pack to reduce oil consumption using average quality oils. The compression ratio was bumped from 15.5:1 to 16.3:1 in the process, which was useful in cold starts for truck applications. Wider main and rod bearings were also added. Emissions controls entered the fray and the DTI466B (the “I” for intercooled) emissionscertified engines for California 466B used an air to water intercooler. The DT466B and DTI466B still used the AMBAC 100 pump and the number of ratings expanded to span 160-210 hp.
In 1982, the DT466C was introduced. There were numerous small internal updates including larger diameter lifters and a higher-flow lubrication system. The injection pump changed to a Bosch MW inline and both turbo and turbo intercooled engines were offered. Two intercooled engines were offered in this line, the new air to air (DTA466C) and the precious DTI466C air to water system.
The original DT466 family underwent a major transformation for 1993 after several years of