When it comes to door locks at very cold temps, I have found
that adding oils of any type to locks is not a good idea. 

I tried it a few times, but it just messed them up. The oil collects
dust, grime, etc., making even the graphite that is in there
a problem.

Spray them out with a good cleaner, then gasoline. I pulled the door
panels off, then wrapped a rag around the lock to prevent splashing.
Use a small oil-squirter-can to pump the gasoline in there. Then I
used 70% alcohol to clean it up real well. If you try turning the 
key when it is this clean, it will prob. squeek. Then I just use
lots of graphite to lubricate it. Mostly from a pencil (too cheap
to spend $3.00 on a tube of graphite). A little alcohol will get it 
deep into the lock.

My locks turn fine at 15 below, just as easily as when hot out.
The window cranks are another matter. I have to roll them
down to see outside sometimes, as the windshield will frost
over on the inside.

--- Chris Chubb (cchubb@ida.org)
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