Trying to Remember a Post Apocalyptic Series from the 1980's
I am trying to remember a book I had as a kid. I think it was a 4 part series but I only had book 3 (because I was a kid). It was a post apocalyptic setting, where this group of survivors (if memory serves) had a commune that was very well prepared because they had someone (or people) who set aside stuff they would need after the apocalypse. I remember they traveled, and they 'miraculously' (in hind sight) had supplies to keep their vehicles running, defend themselves, and I guess provide food.
Any insights to a book series that matches my description would be much appreciated.