My bedroom door has squeaked for six months. Six months. Every night when I got up to use the bathroom, the hinge would announce my departure to the entire house with a sound like a distressed seagull. I kept meaning to fix it. You know how it goes.

WD-40 is not the answer. WD-40 is a solvent and water displacer, not a lubricant. It quiets the squeak for about three days by temporarily coating the metal, then evaporates and leaves the hinge drier than before. You end up in a cycle of spraying it more and more often.

What Actually Works

White lithium grease — a few dollars at any hardware store — is the proper fix. It is a thick, long-lasting lubricant designed for metal-on-metal contact. Spray a tiny amount on the hinge pin (the vertical rod the door rotates on), work the door back and forth a few times to spread it, and the squeak is gone. For good. I did this once on my bedroom door three months ago and it has been silent ever since.

No lithium grease? Petroleum jelly (Vaseline) works in a pinch. Pop the hinge pin out partially — tap it up from the bottom with a nail and hammer — smear a thin layer on the pin, push it back down. Not as permanent as lithium grease but lasts months instead of days.

The One Thing Nobody Tells You

Sometimes the squeak is not the hinge at all. Check if the door is rubbing against the frame. Look for wear marks on the top or side edge of the door. If you see them, the fix is tightening the hinge screws (they loosen over time from the door’s weight pulling on them) or, if the screws spin without tightening, jamming a toothpick coated in wood glue into the screw hole, breaking it off flush, and re-driving the screw. The toothpick fills the stripped-out hole and gives the screw threads something to bite into.

My bedroom door is silent. My wife can sleep through the night. Six months of noise fixed in six minutes.