DETROIT: General Motors Co said on Tuesday it will spend US$877 million to overhaul its pickup truck factory in Flint, Michigan, capping a series of investments to keep production of profitable large pickups and sport utility vehicles rolling through a significant model change expected in 2018. The Flint investment is part of a plan to expand three U.S. truck plants to install new assembly lines, body welding shops and paint operations for future generations of Silverado pickups and SUVs such as the Chevrolet Tahoe and Cadillac Escalade, while still running the operations that build current models.