Door hinges, lock mechanisms, boot latches, bonnet latches, and various pivots throughout the vehicle all need periodic lubrication. Squeaky doors are the most obvious symptom, but worn latches that fail to secure properly are a serious safety issue – a boot or bonnet that pops open at speed is dangerous. Annual lubrication takes 15 minutes, costs almost nothing, and prevents wear that eventually requires part replacement.
The Right Lubricant for Each Job
Different surfaces need different lubricants. Use white lithium grease on door hinges and moving metal-to-metal parts – it stays in place, does not run off in heat, and resists washing out in rain. It is the workhorse lubricant for vehicle mechanisms. Use silicone spray on rubber door seals and plastic latch bushings – it lubricates without degrading rubber or plastic and prevents seals from sticking to the door frame in cold weather.
Use graphite powder (not oil) inside lock cylinders. Oil attracts dust and grit, which eventually forms an abrasive paste that wears the lock pins and gums up the mechanism. Graphite is dry, slippery, and lasts for years. Lockwood and similar brands sell small graphite tubes specifically for this purpose. Avoid silicone spray inside locks because the propellant residue eventually causes the same gumming problem as oil.
What not to use: never use WD-40 as a long-term lubricant. WD stands for “water displacement” – it is primarily a solvent that displaces moisture, with only mild lubricating properties. It evaporates quickly, leaving the surface drier than before. Never use engine oil or gear oil on door hinges; it runs everywhere and stains paint. Avoid grease in lock cylinders for the same reason.
What to Lubricate
Work through this list once a year (or every 6 months in coastal areas where salt air accelerates wear): door hinges (upper and lower hinge pins on each door, including rear doors), door check straps (the arm that holds the door open at fixed positions – apply grease where the strap slides through the body bracket), door latches (the rotating mechanism inside the door at the rear edge – the manual shows access through the door shut face), the striker plate on the door frame (the U-shaped piece the latch grabs onto), bonnet latch and secondary catch (the safety catch you have to release manually), boot latch and release mechanism, fuel filler door hinge and any latch springs, and the seat slide rails if they are stiff.
Apply lubricant sparingly and wipe off any excess – excess grease attracts dust and just creates a mess. Work the mechanism several times after applying to spread the lubricant through the moving parts. For locks, insert the graphite applicator into the keyway, give a small puff, then insert and turn the key several times to distribute the powder.
Frequency and Climate Considerations
Annually is sufficient for most vehicles in most climates. Coastal vehicles exposed to salt air need more frequent attention to prevent rust formation in the mechanisms – every 6 months is a good interval. Vehicles parked outside year-round need more attention than garaged vehicles. Trade or commercial vehicles where doors get heavy daily use (taxis, delivery vans, courier vehicles) benefit from quarterly attention to door hinges specifically.
Diagnosing the Source of a Squeak
If a door still squeaks after lubrication, the squeak may not be from the hinges themselves. Common alternative sources include the door check strap (which has its own pivot points), the rubber door seal rubbing on the body, or even the dashboard rattling against trim panels. Have someone open and close the door slowly while you listen – the source is usually obvious once you isolate it.
For specific access procedures and lubrication points by model, MechanicMate offers PDF workshop manuals for over 960 models at mechanicmate.net/shop.
— MechanicMate . Questions or a second opinion? [email protected].