Additionally, they state that the hardened cylinder sleeve is more durable and wear resistant than a softer, cast-in wall.

From 1984 until late 1995, the DT engines used a Bosch pump-line-nozzle (PLN) mechanical direct fuel injection system.

In 1994, due to tightening emissions regulations, the engines were redesigned to use electronically controlled unit direct fuel injection.

From the time the United States Environmental Protection Agency's 2007 emissions regulations went into effect, the Navistar DT engines were available in three configurations in what turned out to be their final generation prior to discontinuation.

Modifications from the civilian versions included diamond-coated (metal nitride coating) injectors[citation needed] to enable the engines to run on JP-8 fuel.

[8] Other Variants: In 2004, the entire DT family of engines was updated to meet 2004 emissions standards set out by the United States Environmental Protection Agency.

Changes to the engines included a new turbocharger (called EVRT, for "Electronic Variable Response Turbocharger") with movable turbo vanes to improve boost and reduce lag, a new, electronically controlled hydraulic unit fuel injection system, Exhaust Gas Recirculation with heat exchanger to compensate for improved thermal efficiency, and new four-valve cylinder heads.