It seems like a natural progression. General Motors Corp. already builds trucks with Isuzu Motors Ltd. at its plants in Shreveport, LA, and Janesville, WI, so expanding the relationship to include diesel engines for trucks shouldn't surprise.

The partners announced recently that they will launch a joint venture to build a new plant in Moraine, OH, for production of the next-generation 6.6L turbodiesel engine for medium-duty pickups. The venture will be called DMAX Ltd., a name derived from "diesel, maximum power."

The engine will replace GM's aged 6.5L turbodiesel, now used in light-and medium-duty pickups, as well as in the Chevrolet/GMC Suburban and Tahoe/Yukon sport/utility vehicles (SUVs).

GM maintains that the initial volume will target "work truck" applications, but the prospect of a more efficient, cleaner-burning turbodiesel for the bustling SUV market, where 12 mpg (19.6L/100 km) often is the norm, surely is attractive to GM.

The new engine will employ direct fuel injection and common-rail fuel delivery, as well as a new 4-valve cylinder head design that also increases efficiency.

Volume from the new 650,000-sq.-ft. (60,385-sq.-m) Moraine facility, to be constructed near the engine plant that produces today's 6.5L turbodiesel, is pegged at 100,000 units annually, with production to double by 2004.

Overall investment will exceed $350 million. The plant will require approximately 700 employees, including the 300 workers currently operating the Moraine engine plant that built roughly 65,000 diesels in 1997.

Japan's Isuzu, which is 37.5% owned by GM, figures prominently in GM's diesel technology plans. In November 1997, GM announced as part of the reorganization of its North American-based Powertrain Group that Isuzu would be solely responsible for development of diesel engines.

Isuzu will have a controlling, 60% stake in DMAX, and is expected to use the engine in its own vehicles as well. - Tom Murphy and Bill Visnic