Which lubricant should I use on a lock?
Which lubricant should I use on a lock?
A dry lubricant — powdered graphite or a PTFE spray. Oil and general penetrating sprays gum locks up and are the classic way to ruin one.
A pin tumbler lock relies on five or six small spring-loaded pins sliding freely in narrow chambers, and any lubricant that stays wet becomes a trap for the dust and grit that a key carries in. Over months that paste slows the pins until the key has to be jiggled, and then until it does not work at all — a lock that has been oiled is a common call-out. Water-displacing penetrating sprays are worse than plain oil in one specific way: they dissolve and wash out the dry lubricant that was applied at the factory, then evaporate. Manufacturers publish their own guidance, and it differs — some now specify PTFE and advise against graphite in their cylinders — so the maker's instruction beats the general rule.
The options, ranked
| Option | Good at | Bad at |
|---|---|---|
| Dry PTFE lubricant | Leaves a dry film that does not attract dust, and it is what most modern lock manufacturers specify. | Needs reapplying occasionally, and the carrier solvent must be allowed to flash off. |
| Powdered graphite | The traditional dry lubricant for pin tumbler locks, and effective. | Messy, marks hands and clothes, and some manufacturers now advise against it in their own cylinders because it can clump. |
| Oil or grease | Nothing in a pin tumbler cylinder. | Collects dust and grit into a paste that jams the pins, and it thickens in cold weather. |
| General penetrating spray | Frees a seized mechanism temporarily. | Washes out the factory dry lubricant and then evaporates, leaving the lock worse than before. |
Technique that changes the outcome
- Puff graphite or spray PTFE into the keyway, insert and withdraw the key several times, then wipe it
- Lubricate the latch and the strike plate as well; the noise often comes from there
- Clean a sticky key rather than lubricating around it
- Check the maker's advice for high-security and electronic locks, which is often specific
What goes wrong
- Oil, grease or a general penetrating spray in a cylinder
- Forcing a key that has become stiff — that is how keys snap in locks
- Over-applying graphite, which clumps and jams the pins
Compiled practical guidance rather than a published standard. Product formulations vary by brand and market, so read the label — and where the work is structural, electrical or gas, the regulations that apply where you are govern rather than anything here.
Other lubricant questions
| For | Use |
|---|---|
| A bike chain | Wet lube for wet conditions, dry lube for dry and dusty ones, wax if you want the cleanest and lowest-friction option — and not a general penetrant. |
| A squeaky door hinge | A drop of light machine oil or a smear of white lithium grease on the pin — and lift the pin out to clean it, which is usually the actual fix. |
| A seized bolt | A dedicated penetrant or a 50/50 acetone and automatic transmission fluid mix, plus time, heat cycles and shock — and anti-seize on reassembly. |
| A squeaky floor | Talc, graphite or powdered soapstone worked into the joint as a stopgap — the real fix is screwing the board down to the joist. |
| A sticky drawer | Paraffin wax or beeswax on wooden runners, dry PTFE on metal ones — and never oil on wood. |
| Rubber seals | Silicone grease on most rubbers, and a PTFE or fluorosilicone product on silicone rubber itself — petroleum products swell and destroy natural rubber and EPDM. |
| A garage door | White lithium grease or a garage-door lubricant on rollers, hinges, springs and bearings — and not on the track, which should be clean and dry. |
Common questions
- Which lubricant should I use on a lock?
- A dry lubricant — powdered graphite or a PTFE spray. Oil and general penetrating sprays gum locks up and are the classic way to ruin one.
- What should I avoid?
- Oil, grease or a general penetrating spray in a cylinder Forcing a key that has become stiff — that is how keys snap in locks Over-applying graphite, which clumps and jams the pins
Related pages
- Which lubricant should I use on a bike chain? Wet lube for wet conditions, dry lube for dry and dusty ones, wax if you want the cleanest and lowest-friction option — and not a general penetrant.
- Which lubricant stops a squeaky door hinge? A drop of light machine oil or a smear of white lithium grease on the pin — and lift the pin out to clean it, which is usually the actual fix.
- Which penetrating fluid frees a seized bolt? A dedicated penetrant or a 50/50 acetone and automatic transmission fluid mix, plus time, heat cycles and shock — and anti-seize on reassembly.
- What should I put on a squeaky floorboard? Talc, graphite or powdered soapstone worked into the joint as a stopgap — the real fix is screwing the board down to the joist.
- What should I put on a sticky drawer? Paraffin wax or beeswax on wooden runners, dry PTFE on metal ones — and never oil on wood.
- Which lubricant is safe on rubber seals? Silicone grease on most rubbers, and a PTFE or fluorosilicone product on silicone rubber itself — petroleum products swell and destroy natural rubber and EPDM.
- Which lubricant should I use on a garage door? White lithium grease or a garage-door lubricant on rollers, hinges, springs and bearings — and not on the track, which should be clean and dry.
Sources
- Typical range compiled from manufacturer specifications — At One Place