DETROIT (Dow Jones)--General Motors Corp.'s (GM) vice chairman said Thursday the auto maker will bring more diesel engines in various vehicle segments to the U.S. in the coming years, but warned that diesel is not a panacea for meeting fuel economy standards.
In a video message on GM's Web site, Vice Chairman Bob Lutz said the auto maker will introduce a V-6 diesel engine for crossover utility vehicles and light duty trucks and a 4.5 liter V-8 diesel for light duty sport utilities.
GM already has announced it will offer a 4.5 liter V-8 diesel engine in its half-ton full-size pickup trucks. Currently, diesel engines are available in the three-quarter-ton heavy duty versions of the pickups.
Diesel engines are more fuel-efficient than gasoline engines and auto makers are looking for ways to deal expected increases in federal fuel economy standards.
GM, along with other auto makers, offers diesel engines on many car models in Europe, a region where half the passenger cars sold are powered by diesel engines.
But diesel engines typically are more expensive than gasoline engines and require treatment of particulates and nitrogen oxide emissions, which add cost.
With the U.S. making the emission rules for diesels even more stringent, the benefit related to the upfront cost becomes a question mark.
"The good news is the standard can be met, the bad news is that meeting these standards is about another $2,000 to $2,800 of emissions hardware and control systems on top of the already existing premium of a diesel engine over a gasoline engine, which is anywhere between $1,000 and $2,000," Lutz said.
Lutz also said further improvements to gasoline engines narrow the advantage diesels bring.
He said that while there's a lot of hype on diesel engines now, he urges some caution.
"Do not assume that the diesel engine is the panacea and is going to make everybody get to a fleet of 36 miles per gallon and all you have to is convert everything to diesels and you're home free," he said. "I wish it were that simple."
-By Terry Kosdrosky, Dow Jones Newswires;