Exterior locks should also be lubricated, such as with powdered graphite. An exterior lock that never gets used is more likely to collect dirt, moisture and other gunk that can make it harder to ...

To unlock a frozen door lock, use a graphite-based or bike chain lube instead of WD-40, says mechanic Bob “Motormouth” Weber.

Stuck door lock? Use graphite lube, not WD-40 Getty Image To unlock a frozen door lock, use a graphite-based or bike chain lube instead of WD-40, says mechanic Bob “Motormouth” Weber.

Stuck door lock? Use graphite lube, not WD-40 Getty Image To unlock a frozen door lock, use a graphite-based or bike chain lube instead of WD-40, says mechanic Bob “Motormouth” Weber.

Graphite has long been a popular lube choice, but we like to use bike chain lube. Many of our readers and locksmiths swear by Tri-Flow lubricant. Q: Timing is everything.

A: Although WD-40 is magic stuff, it is not the best choice to lubricate automotive door locks and linkages. Although it does a good job of cleaning and temporary lubricating, it goes away, so it ...