Looking for a new fuel tank cap for your GMC TopKick? We've got you covered with options for non-vented, locking, and vented caps. Choose from aluminum, brass, and plastic in 2-inch sizes with various thread patterns to fit your truck perfectly. Many are leak-resistant to prevent spills and keep your fuel system intact. Built tough for heavy-duty use, these caps provide the durability and peace of mind you need on the road.