DETROIT -- General Motors says it will spend $632 million to update its Fort Wayne, Indiana, assembly plant so it can make the next generation of full-size pickup trucks with internal combustion engines.

       The investment in new conveyors and equipment in the body shop and assembly areas won't create any new jobs. But GM said on Monday it will keep jobs for about 4,000 people who work at the plant.

       Construction will start in 2024 at the plant, which now builds the Chevrolet Silverado 1500 and GMC Sierra 1500 light-duty pickup trucks.

       GM wouldn't say when the next generation of trucks will go on sale.