My wife and I lived full time through a Rocky Mountain winter wild camping/boon docking every night in our truck. We also explored the High Sierras, Death Valley and plenty of southern Utah - including running the White Rim Trail as the first vehicle through after November snows.
The requirements:
25 feet or less in length 19ft
1. Really good off-road 4x4 not even close to stuck even once, rear and front locking differentials we don't have them but I believe you can fit ARB lockers, winch we have a Warn 12,000lb, decent approach/departure/breakover angles check, 3 point camper mount ours has a four point flex mount but does a similar job
2. Have or be able to be modded for large solar+lithium battery bank. Electricity the main power source. This is an option, as is an induction hob.
3. Bellow/portal access from cab to camper. Certainly possible but would require a custom build
4. Large freshwater/grey tanks, cassette or composting toilet, large diesel fuel tank(s). 80gal fresh (+ remote collection & filtering), 23 gal grey, fresh water Thetford cassette toilet. Space and payload for an aux fuel tank if required we didn't need one.
5. Must be 0F to 110F capable. Check. We saw -10 to 10f for weeks on end in Utah in Jan/Feb. Inch thick fibreglass/foam sandwich built in a female mould Double pane windows, Yes interior or heated tanks and lines Dedicated heat for water tanks. Air conditioning and heater systems that are commensurate with these temps. We have a Webasto DualTop which ran solidly for 3 months and was superb. No A/C but if you really wanted it you could fit it. We found the setting the fans to blow out worked well with vents opened in the right spots.
6. Parts have to still be available. Available in every town across N America
7. A vehicle cab that you don't have to put ear plugs in at 65 MPH and doesn't beat you to death. We cruise at 65 and do just fine
8. If foreign, must be left hand drive and registerable in the US. US Truck
Cost is $121k plus the truck
You'll notice that the first picture depicts a route that you couldn't drive in virtually all the vehicles discussed, and must be one of the finest trails in the whole world. Personally I wouldn't dismiss a popup hard sided camper: I was a buyer/owner before I set up XPCamper in Europe. Ours is the original Prototype 1.1 on a single cab 2007 6.0 F350 with 35" Toyo MTs we get 19mpg (US). We have 480w of solar and 420Ah AGM batteries, lithium is an option. After nearly 10 years in production the V1 is a really refined build now. There is loads of storage, and we managed with all our ski kit, despite having the only single cab in the fleet and no under tray boxes. If you ever did want to explore further afield it will fit in a 20ft shipping container. If you ever have an issue with the truck you swap the bed and camper onto a different vehicle - unlike a coach built camper.
Everyone has their own best set of compromises but having read the whole thread I'm not sure why you ruled out the very first suggestion. Best of luck with your search, happy to answer questions with my owners hat on, or my XPCamper hat on!
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