Here are your basic requirements:
- a 4x4 crew cab pickup with the ability to put mountain bikes in the bed of the truck along with 3 or 4 passengers in the crew cab that can shuttle on rough dirt roads
- And you want to be able to store and lock the bikes in the toy hauler.
So it sounds like a Travel Trailer Toy Hauler (not a 5th wheel Toy Hauler) is what you are looking at.
A 4x4 one ton crew-cab Single Rear Wheel pickup truck with short bed should work out well for you (assuming a Travel Trailer and not a 5th wheel). A one-ton truck costs just a littler more than a 3/4 ton truck so you should consider it. And a modern one should handle most sizes of Travel Trailer Toy Haulers.
A half ton might work also, but that will limit your choice of trailers. You should start learning about the weight ratings of trucks and trailers and how the numbers work (GVWR, GCVWR, GAWR, Tongue Weight). It will help you make a more informed decision (as far as how heavy a trailer you can comfortabley and safely pull).
With a Travel Trailer Toy Hauler you should also learn about different types of "Weight Distribution Hitches".
Have fun figuring it out.
Let us know as you start narrowing down your options and you'll be sure to get lots of advice.
Ed
