SALT LAKE CITY. General Motors is bringing new hybrid and gasoline engine technology to bear to help boost fuel economy of light trucks.

Displacement on demand (DOD) is what Brian McVeigh, general manager for GM’s Fleet & Commercial division, believes should offer the biggest boost to light truck fuel economy. DOD turns engine cylinders “on” and “off” depending on how much power the vehicle needs at any one time. That would give GM’s V-8 engines the ability to sip gasoline like a V-4 in light inner city and steady highway driving conditions, said McVeigh.

“By 2008, GM plans to equip more than 2 million vehicles a year with this fuel-saving technology,” McVeigh said here at a special 2006 commercial product preview event.

“The trick has been to get the engine to switch the cylinders on and off almost instantly, without any loss of power or performance to the driver,” Steve Matsil, vehicle chief engineer for GM, told Fleet Owner. “Then when you combine that technology with a hybrid electric power source, you really boost fuel economy even further in certain applications.”

McVeigh pointed to the company’s full-size hybrid pickup models as an example of how fuel economy can be improved by marrying DOD and electric power together – enabling the trucks to attain 18 mpg in city driving. He said the company plans to expand its DOD and hybrid system into its line of sport utility vehicles within the next two years.