General Motors Corporation (GM:$2.05,00$0.13,006.77%) , union leaders and the Treasury Department have reached an agreement to reduce the failing auto giant's $20 billion retiree medical obligations. The United Auto Workers announced the settlement, which the Journal reported is a linchpin of the automaker's plans to restructure its finances. GM wanted a deal that would cut in half its $20 billion cash obligation to the retiree medical trust. In exchange, the UAW would get a 39%equity stake in the automaker. GM faces a June 1 deadline imposed by the Obama administration to restructure its finances, get concessions from unions and debt holders and slash dealerships. If the automaker cannot meet all of the terms, it will be forced by the government to enter Chapter 11 bankruptcy protection.