WD-40 is a seemingly all-purpose lubricant, degreaser, and water displacer that has helped people loosen stubborn bolts and silence squeaking hinges for decades. There's an old saying that if you need something stuck, you use duct tape, and if you need something unstuck, you use WD-40. While WD-40 is great for getting things to move more easily and more quietly, sometimes it's better to reach for something else. Because WD-40 is an all-purpose product, it's pretty good at a lot of jobs but not necessarily the best at any particular job. Here are five times you should put the WD-40 down and reach for an alternative.