Mailboxes, like any exterior fixture, require periodic cleaning to maintain their appearance and extend their longevity against the elements.
At a minimum, we recommend one yearly cleaning of metal surfaces with a mild general cleaner, followed by waxing with a product such as Nu Finish. This can significantly prolong the life and lustre of any exterior-installed mailbox.
Lock lubrication is also worthwhile preventative maintenance. Types of lock lubrication that can be applied include dry graphite powder (availabe in small tubes) or a teflon spray such as Super Lube. Both types of products are typically available from most hardware retailers. Do not apply WD-40.
Locks can freeze, especially during a rapid temperature drop. Automotive style lock de-icers are an effective solution to this problem.