CHICAGO, Aug. 18 (Xinhua) -- U.S. automaker General Motors Co. (GM) plans to boost production at several factories due to higher sales from the federal "cash for clunkers" program, the company said Tuesday.

    GM spokesman Chris Lee said Gm's Orion plant in Michigan, which makes the Chevrolet Malibu and Pontiac G6 midsize sedans, will pick up a day of production on Aug. 28 while its Lordstown plant near Detroit, which makes the Chevrolet Cobalt and Pontiac G5 small cars, added two days of production on Aug. 21 and Aug. 28.

    According to a Detroit News report, the Malibu and Cobalt have been popular with people trading in older, less-efficient models under the clunkers program, which offers up to 4,500 U.S. dollars to people to scrap vehicles with gas mileage of 18 miles per gallon (mpg) or less.

    The Cobalt, GM's highest-mileage car at up to 37 mpg on the highway, once was among the top 10 vehicles on the "cash for clunkers" purchase list. But dealers say shortages have bumped it from the top 10 list.