My advice would be to take no snacks at all. Plan real meals at stops along the way, choose meat and salad/meat and veg kinda meals that include plenty of satiating fat, and then don't have any food in the car at all. I know when I'm travelling, I snack out of boredom rather than hunger. I have a much better chance of avoiding that trap if there simply isn't anything to snack on.
Good luck with your move!
Zone diet on and off for several years....worked, but too much focus on exact meal composition
Primal since July 2010...skinniest I've ever been and the least stressed about food