Most automotive locks are hardened steel wafers sliding in a hardened steel keyway. They are lubed with waterproof grease. This is unlike many padlocks and home locks, which have ungreased brass parts sliding against steel. These can be usefully lubricated with graphite.
Putting graphite in a greased lock will gum it up. A solvent based spray will redistribute the existing grease, so almost any type will work. An alcohol based lock deicer has the least chance of depositing an incompatible lubricant.
What do you recommend to de-gum auto locks (which used graphite)? Can teflon (triflow) be used for auto locks? Do you use same in door lock and ignition keyhole?