Use high-pressure air from a can of dust remover to remove dust from the dial and shackle areas and to clean your lock. Chemicals and airborne dust particles can settle inside of your combo lock over time. This creates friction in the delicate locking components and lowers your lock's performance.
Put lubricant on the shackle and dial parts if your lock freezes up in the winter. Apply the lubricant sparingly -- you need just a few drops. Let the lubricant sink far down into the lock. Knock the lock gently against a table to spread the fluid throughout the lock and loosen up any frozen or stuck parts.
Turn the dial of the lock many times to distribute the lubricant after applying it. Check the dial or dials as well as the lock and shackle and wipe any extra lubricant from them. Allow the lock to air dry. The lock is ready for use once it is dry.