Spokesman Chris Lee says the some 1,100 remaining workers were informed Friday afternoon of the closing date. The automaker earlier this year announced plans to close the plant by the summer of 2010 or sooner, then accelerated shutdown plans as part of companywide cost-cutting moves.
Union leaders said they expected the plant to close in January or February.
The company recently reduced operations to a single shift. A customer move away from sport utility vehicles to smaller vehicles amid high gas prices led to the shutdown plans.