I am going to go off track here for a second. Do you think you could make it all around with say a 1/2 truck and lance camper in the back?
That's a tricky question. I try to keep our weight at or under the Gross Vehicle Weight Rating (GVWR) of our van (which is 9,500). We have seen and heard of broken frames on many of the smaller trucks but also know of an F250 that cracked its frame twice. The best advice is to do the best you can calculating what the realistic weight of the camper and truck combo is going to be and work from there. 95% of all rigs are at or overweight, even some of the MANs, MOGs etc exceed their carrying capacity. If you prefer off pavement, the constant jarring from all the weight takes its toll. If you prefer pavement, it's better, but some of the worst roads were deteriorated pavement and not the rocky single tracks.
It's not an easy cat to skin. Simple things like moving up to E rated tires = more weight. 10 extra gallons of fuel and/or water, more weight. Spare parts this and extra fluid that, more weight. All those nightly cocktails and tacos, more weight. Ok, maybe that last one isn't necessarily true. I usually tell people to gather every item they want to take into an empty room or the middle of the living room, then sit with it and imagine living with all of that crap for years. We all need to lose weight, plain and simple. The only way most of us deal with it, because we're too stubborn to drop all the useless stuff, is to move up in vehicle class...or buy a diesel because that's what we wanted.
Am I going to tell you to buy a different truck, of course not, but I'm also not going to tell you that you'll be fine either. There are way too many variables but I will share what I've experienced. We know of full sized vans that break 11,000 lbs without issue, we have severals friends in 3500 trucks that are pushing 14,500 lbs. We know of Tundras with non pop-top truck campers and we've been around every truck pop-top truck camper combo conceivable. Everyone one those were conscious of their weight, rig capability, and travel preferences. And, as mentioned above, we have seen many broken frames, failed shocks, snapped camper mounts, and busted axles. We also ran into many off the shelf US and European RVs, mostly Class-Cs. Most of the surfers rarely left the coast, the climbers and hikers stayed in the mountains, the multi-sports travelers and those of us that drive in erratic circles did a lot of both. The coast is mostly paved with short spurs to the ocean. The mountains are a mixed bag and many of the cut over roads, especially the ones that were always the closest and most convenient, were a hot mess...or we just had bad luck when picking them.
I'm not sure this actually answers your question but I have no problem discussing in more detail on another thread or via email or PM.
-John