Originally Posted by caper
I have worked with locks for over 10 years (Kwikset). I would never use WD40. Dry graphite is the only thing needed. It is a good idea to lube the pin area several times a year. You can spray a silicon spray into the latch area of the lock to keep it free. If you find the door hard to close try lubricating the latch area of the lock. A RV tech told me that this area should he lubricated once a month.
Just a reminder there are no pins in these locks they are cheap brass "dic Tumblers", they are flat and thin and can be damage easy, lubrication is one thing but keeping them clean and dry is another. To spray anothing in the keyway is not the right thing to do, all ways apply it to the key then insert it into the keyway and move it in and out a few times til it moves freely, you do not need to flood the cylinder, by flooding the cylinder causes a mess all over the door around the lock.....Example: Our electrical engineer at work ran a call about a lock the\at was not operating properly, after his attemp he called me to help........Ok you may be asking yourself why would he call me well he knows that I am a licensed and bonded locksmith and have the proper tools but this is not my primary job, well to make a long story short he thought that if he applied WD-40 to the lock everything would be ok....
It wasn't WD-40 that was needed but he thought so, he used so much it was running out from the lock and down the door, well needless to say the problem with the lock was not that it needed lubrication it needed to be replaced one of the screws were strip out because someone used the wrong tool to install the lock and it just happen to be a bathroom lock.....YES the customer was lock in the bathroom and could not get out with out help. If you want to do things on your own either ask someone that knows or check the enternet. I am sure this is where herk gets his info if he does not no. One dose not have a plumber do electrical work unless he is trained to do so and that is the way it is in all trades.