What type of pickup truck do i need?

For full timing, you'll want to look for 4 season packages, plenty of storage, and maximum interior space. All this adds up to more weight. Don't make the mistake of buying too small of a truck. Because in a year you'll be buying a bigger one...
My next setup for full timing, after the kids are grown, is a one ton duelly towing a fiver. If I'm gonna spend 5-6 months in something, it better be comfortable or else I'll just stay home.