DETROIT -- Amid growing criticism of gas-guzzling SUVs, General Motors said on Thursday it would add new fuel-saving technology to most of its SUVs and pickup trucks.
GM said that starting next year it will make its new "displacement on demand" technology standard equipment on three SUVs powered by V8 engines, boosting their fuel economy by about 8 percent.
Displacement on demand, or DOD, automatically shuts off half of a V8's eight cylinders, temporarily turning it into a more efficient four-cylinder engine, when the vehicles are cruising at a constant speed or carrying a light load.
DOD will be rolled out over several years and be added to most SUVs and pickup trucks by 2008, as well as to many cars with V6 engines.
GM next year will add DOD to V8 engine versions of the Chevrolet TrailBlazer, GMC Envoy and GMC Envoy XUV SUVs. That will raise their fuel efficiency, currently 15 to 20 mpg, by about 1 or 2 mpg, said GM spokesman Dave Roman.
But that will be far below the 40 mpg that some environmental groups say is possible.
Detroit automakers came under fire this week in a new advertising campaign co-sponsored by a Hollywood group led by syndicated columnist Arianna Huffington and a New York-based environmental group headed by Robert Kennedy Jr., son of the late Sen. Robert Kennedy.
The new TV and print ads that Detroit could help slash the U.S. dependence on foreign oil by more than doubling the fuel economy of cars, trucks and SUVs. But they say automakers refuse to build vehicles that "take America to work in the morning without sending it to war in the afternoon."
GM's Roman said the DOD technology will be added to some mid-sized cars in 2005, and by 2008, it will be fitted on more than 2 million vehicles on the road.
The technology, which costs a nominal amount for the automaker to install, will help GM meet rising fuel economy standards for pickup trucks, SUVs and vans, Roman said.
"It's one of many things in our tool box that we're pulling from," he added.