General Motors announced today that it will close three U.S. assembly plants, and trim or close operations at other plants and facilities by 2008 to help stop billions in annual losses at its core North American auto operations. The closings will cut some 30,000 hourly jobs, up from its original plan of 25,000. Many of the job eliminations come as soon as next year, even though job protection provisions under union contract runs through September 2007. The plan is designed to save $7 billion a year by the end of 2006.Plants being closed in 2006 include Oklahoma City, and the Lansing, MI, Craft Centre, while Doraville, GA is slated to close in 2008. Some shifts will be eliminated at three other assembly plants. In addition, Line 1 at Spring Hill, TN, and Oshawa, Ontario, Car Plant 2, will also shut, although assembly plants on the same property as those two lines will continue to operate. The Moraine, Ohio plant will also lose one shift in 2006.The company said the full range of cuts will eliminate 30,000 hourly jobs through the capacity reductions, and approximately 7 percent of salaried, non-union staff by the end of 2006. GM had about 111,000 hourly U.S. workers at the start of the year.