Which car brand does NOT belong to General Motors?

The car brand that does not belong to General Motors is Ford. Ford is a separate and independent American automobile manufacturer, founded by Henry Ford in 1903, and has been a rival of General Motors since its inception. Ford has its own distinct history, lineup of vehicles, and manufacturing facilities, separate from the brands under General Motors such as Chevrolet, Buick, GMC, and Cadillac. Therefore, Ford stands out as a major competitor in the automotive industry, rather than being a part of General Motors.