Going to stick with my Honda Accord and my Trek 7.2 bicycle. The honda gets good gas millage so get as far as I can get with that then pull the Trek out of the trunk and continue on. Me and my girlfriend started bicycle camping last summer and did a weekend camping trip. 30 miles away 60 miles round trip. We had everything we needed for the weekend and more.
I saw a 2008 Jeep Liberty diesel for sale on craigslist (Phila., PA). There are ways to "jump" the electronics on post 1973 diesels, check Youtube and by all means read James Wesley, Rawles. That would be an exellent G.O.O.D. vehicle. You will be able to use bio-diesel, and for a short time after SHTF, #1 Fuel oil (heating oil), but it will eventually clog your filter and/or injectors.