Any sort of liquid lubrication would probably cause the tumbler to be
gunked up as dust and dirt collects. A small amount of graphite powder
every now and again is probably the only thing you can do. Keeping the
key free from dirt is a good idea too.

Im anonymous wrote:
>
> Ok, so I'm very anal and particular...What do you think about putting
> some sort of lubricant on the key to prevent wear from inserting and
> removing the ignition key repeatedly?
> I know it would take forever to wear one out....just a thought.