What to Lubricate on a Gate and What to Leave Alone
Lubrication Is Not Automatically Helpful
The instinct when something squeaks is to spray oil at it. On a gate in a sandy coastal environment that instinct is frequently wrong, because a wet lubricant on an exposed surface becomes a sticky trap for airborne grit. The resulting paste is more abrasive than the dry surface was. Choosing where to lubricate, and with what, matters more than how often.
Enclosed Parts Take Grease
Sealed or shielded bearings, roller assemblies with a grease point, and lock mechanisms behind a cover are protected from grit and are exactly what a proper grease is for. These parts benefit from being greased on schedule, and a marine grade product is worth the difference because it resists being washed out and displaces water rather than trapping it against steel.
Exposed Pivots Take a Dry Film
An open hinge pin, an exposed pivot, or a latch that sits in the weather is better served by a dry film lubricant, typically a product that carries a solid such as PTFE in a carrier that evaporates. It leaves a slippery surface that grit does not stick to. It needs reapplying more often than grease would, and that is a fair trade for not building an abrasive paste on the one part you cannot easily clean.
Leave the Track Alone
The ground track of a sliding gate should be clean and dry, not lubricated. Oil in a rail collects sand immediately and turns a channel that merely needed sweeping into one that has to be dug out. If a gate is running badly on a track, the answer is cleaning, checking the wheels, and checking alignment, in that order.
Squeaks Are Diagnostic, Not Just Annoying
A squeak that reappears quickly after lubrication is telling you the surfaces are worn rather than dry. A hinge that has worn oval will quieten for a few days and come back, and each round of lubrication buys less time than the last. That shortening interval is the signal that the part needs replacing, and it is a useful piece of information rather than a nuisance to be sprayed away.