Dog, you need a 3/8" sqaure drive to get the drain plug out. It is actually metric, but a 3/8" extension works fine. Lots of guys have had a trainwreck of a time getting the factory filter off. It is way too tight from the factory. You might make the dealer loosen it so you can hand tighten it before you leave with it. I have taken mine off with gloved hands and reinstalled it that way every single time, so I have no idea what type of wrench fits or works the best. Hope this helps.
EDIT: Rotella is fine, have run it all winter in WI for a couple years. Just plug it in when it gets real cold (20* or lower for me) and you will be fine.