This thread has gone on too long. take it from a locksmith, wd 40 will not
damage your lock, and if the problem is occuring while it is raining, wd 40
will work incedibly well for solving this. Yes, it does leave a residue, but
just give it a tiny squirt and work the key in and out a little. if you want
to get technical, post a question for this on the locksmith ng and you will
hear from every locksmith from austrailla to CA. IMO, wd 40 works fine, if you
have access to super lube dri - film, even better. Wd40 you can pick up in any
store and will solve this.
Gasoline or alcohol is great for your car and your drink, not for you locks.