This is one of those movies that I first saw as a ten-year-old and the recollection of it turns out to be much better than the film actually is. The poster is what I think really sold this movie.
Based on the novel (much better book) by Roger Zelazny (The Chronicles of Amber), it's the tale of a group of survivors (including Jan Michael Vincent and George Peppard) after World War Three and how they try to make their way from Arizona to Upstate New York in this huge tank-like vehicle. They encounter raging storms, giant scorpions, man-eating cockroaches and some unfriendly human survivors. I think the whole cockroach segment is the best part of the movie.
As post-apocalyptic movies go, this gets just an "okay