GM Delays Innovative New Diesel Truck Engine

GM Delays Innovative New Diesel Truck EngineBy Richard TruettAutomotive NewsGeneral Motors' deteriorating financial situation has caused the company to delay one of the most advanced engines that it has ever designed, a 4.5-liter diesel for light-duty trucks.Truck enthusiasts were eagerly awaiting the engine, which would have started production next fall at GM's plant in Tonawanda, N.Y. The engine has unique cylinder heads that eliminate the intake and exhaust manifolds. Its lightweight block has advanced castings for the crankshaft-bearing journals and oil-circulation system.
GM had planned to install the engine in the Chevrolet Silverado and GMC Sierra pickups. The result would have been a fuel-efficient truck priced for less than the heavy duty diesel-powered trucks available now.
GM has been awarded several patents for the engine design, and early tests have shown the new motor to be as smooth and quiet as a gasoline engine. Development of the engine was far along when the decision was made to put the program on hold.Garavaglia said GM would consider a joint venture with another company to build the engine if it was a "win-win" for both companies.
If GM decides to revive the engine, it would likely take at least a year for it to enter production. Meanwhile, GM will not be out of the diesel truck business. The company will continue to offer the 6.6-liter Duramax engine in heavy-duty pickups and modify it as necessary to meet tougher emissions standards.
GM also has just launched Two Mode hybrid versions of the Silverado and Sierra, which get an EPA rated 21 mpg city and 22 mpg highway. The 4.5-liter diesel would have raised the trucks' fuel economy into the mid to high 20s mpg.
Last month, GM scrapped plans to build an engine plant for the upcoming Chevrolet Volt plug-in hybrid and Cruze small car. Instead, the engines will initially come from a European factory while an existing factory in Flint, Mich., is retooled to make the new engines. GM Powertrain Group Vice President Tom Stephens recently said that all of GM's future production plans are constantly being re-evaluated.