UAW members voted 74 percent in favor of the deal that includes giving up cost-of-living raises and performance bonuses and one paid holiday in 2010 and 2011.
The deal also suspends tuition assistance and dental coverage, and reduces prescription drug coverage, the Detroit News reported Friday.
"It was a tough, but necessary vote," Local 599 leader Terry Everman in Flint, Mich., told the newspaper.
UAW President Ron Gettlefinger said the union had done its best to prevent a bankruptcy filing. Members, however, were "prepared for what eventually happens," he said at a press conference, The New York Times reported.
GM, however, is not out of the woods yet. Creditors have until 5 p.m. Saturday to accept a deal that trades $27.2 billion of debt for 10 percent of the restructured company with a warrant to buy an additional 15 percent at a later date.
In the latest restructuring plan, the U.S. government would likely end up with 72.5 percent of GM, while the UAW would end up with 17.5 percent. Bondholders would receive 10 percent, the Detroit Free Press said.