Also, keep your fuel as full as possible because you never know when you might get stranded due to pile ups, interstate shutting down, or your own mistakes. I don't let my truck get below half a tank during winter months. Half a tank for me is 150 gallons though. Depending on what you're driving, you may want to top off more frequently if practical. Great info by the way. I keep tire chains in the truck but never considered keeping chains/sand/shovel in the car for some reason.