It’s been just over three weeks and 1,400 miles since we began to call this new rig “home.” Now that we’ve settled in, it’s time for our virtual housewarming, if you will. Here, we break down all the nitty gritty details of our new truck, providing a full spec list and systems breakdown. So when you see us on the road and wonder, “What the heck IS that thing?!,” now you have a place to go to get a sneak peek and answers to all your burning questions. If we left something out, please let us know in the comments below.
First of all, if you haven’t already read our post on why we chose an expedition vehicle as the platform for our new home, you can learn all about our rationale and reasons for going with a truck this beefy.
Don’t feel like reading? Check out this short video.
THE CHASSIS
Our truck is based on the M1083 variant of the FLMTV (which is the family of light medium tactical vehicles for the US military). She’s 29 feet long, with a 6×6 drive train, and is powered by a 3126 Caterpillar engine mated to a commercial Allison C7 transmission.
In her past life, she was a military gun truck set up for heavy cargo, as indicated by the 70,000-pound rear leaf springs. She rides on 395 Series Michelin tires mounted on 20” rims, for an overall tire height of 48 inches. The rims can be split for field-changing tires, and the central tire inflation system (CTIS) allows us to change tire pressure from highway to trail, sand or mud, or even to continually fill one tire in an emergency.
REDEFINING “SUPER-DUTY”
As with most military vehicles, every aspect of her is solid, overbuilt and ready to be field-serviced using simple tools. With the cabin and 254 gallons of fuel, along with 145 gallons of water, plus personal possessions, she weighs right around 11-12 short tons (~23,000 pounds).
According to her specifications, she can climb a 65% grade and traverse four feet of water without any modifications. So far, we have taken her over boulders, across worn washboard gravel roads, through ditches and (more frequently than we care to admit), over curbs and highway exit medians when we’ve missed an exit…Ooops. All without effort and a barely perceptible passenger feel. Our first trip of 1,400 miles, mostly highway and city driving, resulted in an average of 6.88 miles per gallon. As she’s been breaking in, we are now averaging 8 miles per gallon.
THE CAB
The cab was originally designed for a three-person crew, so with the middle seat removed, there’s over 40” between the passenger and driver seats. Where there used to be military gear and ammunition boxes behind the seats, we now have ample storage space for crates of gear and a place to hang jackets. The cab is not luxurious; it’s quite minimalistic, but it does have good AC and heat, as well as air-ride seats (which helps ease the transition between the smooth Mercedes Sprinter ride and this quite nicely).
Between the cab and cabin is a solid, structural, insulated and locking cab-to-cabin access door, allowing easy access while underway. It’s a bit more of a contortionist maneuver than the Sprinter van, but it’s not bad and will certainly keep us limber. The ability to close off the cab from the cabin completely is not only good for temperature regulation, it’s also a lot safer.
THE CABIN
The full cabin, manufactured by Global Expedition Vehicles in Nixa, Missouri, measures 20.5 feet long (including 16.5 feet of cabin living space along with a 4.5 foot gear garage). It is 8 feet wide and 6 feet, 7 inches tall. This truck was originally a spec-build by GXV, so the finishes are not of our choosing and some of the layout choices had be modified to accommodate our needs. For instance, the truck was originally only intended to have exterior storage beneath the queen size bed. Cleverly, GXV was able to extend the rails of the chassis to accommodate our much larger gear garage, sandwiching the structural composite to the back of the original cabin for a nearly seamless end result.
Within the cabin itself, a 16.5’ x 8’ x 6’7” rectangle, we have a spacious wet bath with a Thetford cassette toilet, a slate stone sink with small vanity and mirrored medicine cabinet.
An almost 6 foot long galley has plenty of pantry storage, a deep stainless steel sink and quartz countertops. We opted for a Webasto diesel stove because of its energy efficiency. Induction is great, but if you plan on living off-grid as much as possible, you will find the energy-suck astounding. Diesel isn’t without its downside, as it is hot and takes a long time to heat up. Therefore, we also use two plug & play induction burners in the summer months or when we have access to shore power.
On the other side of the cabin, from fore to aft, we have a Vitrifrigo two-drawer refrigerator/freezer, above which sits a combination washer/dryer in its own custom cabinet. For dining, we have a booth-style dinette, seating four, and a high/low table converts to a sleeping berth. Shoes and extra pantry items can be stowed beneath the seat benches.
At the far end, there is an east-west queen-sized bed, elevated 48-inches to allow water tankage, the heating system, inverter and solar controllers, along with a spacious under-bed garage accessed by heavy-duty doors on both sides of the vehicle.

The integrity of the thermal cabin envelope is maintained by three Armor Vision double-paned, steel-framed windows, which are among the strongest and heaviest-duty available. They can be opened fully, screened-in or used in full black-out mode. Also, they can be locked in a cracked-open position to allow air-flow while maintaining security, which is particularly nice when we’re driving and Bethany is making coffee in the back, or when we are using the Fantastic Vent fan to create optimal air circulation. A note on our Fantastic Vent: If given the choice, we would have gone with the non-automated version. The 7350 model seems nice, but when the rain sensors detect condensation at 2am and interpret it as rain, the whole thing shuts down. Plus, you have to locate the remote in order to operate it. Some things are better off left to manual operation.
THE GEAR GARAGE
Aft of the bed, sealed off from the main unit, is our gear garage. The gear garage is full width, full height, and 4.5 feet deep. It accommodates four bicycles held vertically using Thule Sidearm carriers, plus nearly all of our other sports gear from paddles, backpacks, and kite-boarding kit to fitness equipment, outdoor paraphernalia and snow gear. The interior is criss-crossed with seat track so we can easily change the configuration of tie-down points as necessary. We also stow our spare tire in here, as we did not want to add length to the vehicle by storing it outside, and it would have interfered with the way our garage door is operated.
The garage is accessed via a custom full-size lift gate, which can be lowered by winch to 23” above ground, creating an access ramp. When held parallel to the ground, it transforms into what we fondly refer to as “Party Mode,” an 8’ x 6.5’ patio which supports up to 1,500 pounds.
SYSTEMS
We have a 16,000 BTU air conditioner mounted on the roof.
The heating is hydronic, powered by a Webasto Thermal 90 unit, which supplies hot air as well as hot water. Since our hydronic unit is connected to the engine’s cooling system via a heat exchanger, running the engine creates hot water and cabin heat. In reverse, heating the cabin creates hot water and pre-heats the engine for ease of start-up in extreme conditions. Since we plan to take full advantage of winter in the American and Canadian Rockies, and eventually Patagonia, heat is not only for sheer comfort, but necessity. In temperatures below zero, a loss of heat could create a life or death situation that we wanted to be prepared for with multiple back-up systems. Should our main heating system fail, our diesel stove will easily warm the cabin and, should that too fail, we can run our A/C in reverse, which puts out 5,000 BTUs of heat.
On the roof, we have three 100-watt solar panels mated to an Outback controller. On an average day, the sun provides us with enough power so we do not need to run the 3.6 kW generator, which is mounted in a sound-proof box on the chassis. The solar power is stored in three AGM D8 batteries with a total capacity of 765 amp hours. On our maiden voyage with her, we stayed in Wisconsin for a week in partial shade and never needed to plug in or run the generator.
OTHER EXTERIOR FEATURES
- Manual awning
- Triple backup cameras to provide visibility left, right and behind the truck
- Roof racks for stand-up paddleboards
- Above-the-cab storage box for inflatable boards and other weatherproof gear
- 50” light bar to light up the road
- The original military headlights were replaced with LED headlights
- Locking exterior storage lockers for tools, cords and our ladders
- Slide-out aluminum retractable stairs for cabin entry, along with a custom retractable mini-step GXV built to help Bethany (5’4”) be able to reach the cabin door when the stairs are not deployed.

Have a question or want to know something we missed? Ask us below! We are now headed to Glacier National Park for a few weeks before doing some work in Albuquerque. Follow us on Instagram for all the latest.
Hi, My Wife and I are very interested in this. If it’s not to much to ask. What was the cost of the cabin? We know ours will be different, but we would like a rough estimate before we get started.
Thanks!
You bet.
Have a question can u text me please
Not a problem good to hear from yall and to see yall doing well
Awesome, will let you know if we swing through there at some point this year. Thx!
Yes still in arizona. Also have the people i need for different issues involving trucks
Hey, hope you’re doing well. Still in AZ? Great to know we can reach out if there’s an issue. She’s been purring wonderfully for us :).
I may be able to help with issues you have with your off road rv. Since i was the one building them
Good question – GXV researched and designed that particular mod. Perhaps backchannel us with your budget and what you’re looking for and we can keep our eyes and ears peeled for you :). Twoifoverland@gmail.com.
We are also interested in purchasing an M-1083. I don’t think the question has been answered, but do you know who manufactures the air intake that GXV used on your truck?
The Kenworth that GXV has been building on is out of our budget, otherwise we would consider going that route.
This is the biggest sticking point for our decision. We want to be able to move between the cab on the camper without having to exit the cab.
Toby: where do you source locking axles for the MTV and how much is the conversion?
Thanks!
Good questions. Maybe we can link up when we’re back in Colorado sometime so you can see these specs for yourself. The air intake was modified by GXV to allow the cab pass-through, not sure what the intake system is specifically. We definitely got plenty of room for all the gear we could want/need. We now have the high speed gears but no Detroit lockers. We were fortunate that our cab came with a phenomenal AC and heating unit. :).
Hi guys!
I have been working on my M10835A1 for the past 6 months.
Can you tell me what the air intake system is?
I would love to loose the OEM system and get all that space for gear.
Do you have the high speed gears and the Detroit Lockers?
I have a guy that put mine in for a very reasonable price.
Are you planning on adding AC?
I did and it was a gigantic pain in the rear.
Looking ad adding a WVO system after I leave Colorado as they are not legal here as well as a water / methanol injection system.
Best wishes from Colorado!!!! Safe travels! Thanks for the great website & pictures!!!
Good questions and good luck with your auction hunt!!! Our truck was purchased by GXV with no known issues. That said, we did every preventative replacement we could (gaskets, air lines, hydraulic lines, full transmission and engine service, etc). We have had a few minor problems with it along the way and parts/service are never far from the highway. (Needed to replace an injector, fix an air leak, replace an air can, and, for preventative measure, we replaced all the drive shafts and U-joints because we noticed one was loose. Yes, the frame was extended to accommodate the addition of our gear garage. We changed the air intake and filter type and location, and moved the spare tire into the gear garage to accommodate the pass-through. Will definitely check out the organizations you mentioned. Keep in touch as you get closer to getting your vehicle! Would love to link up when we are up there this summer. Always appreciative of those willing to meet and share driveway space :). Thank you!
Thank you for sharing all of this information. My wife and I have been watching the auctions for about a year now and feel we are getting close to making a purchase. I saw one with all green stars go for $5100. Two weeks ago. Wish I had put in a bid.
May I ask… (well several) did your truck have green stars all the way, or did you get one with some known issues? Also what are your thoughts/conclusions on sourcing parts? My biggest concern is how will o get parts for this truck if I need them. Did you have the frame extended? Obviously you deleted the tire lift, what about the air intake, I did not see it in any of the photos I have seen nor in the video. What else did you have to move to make your pass through.
Lastly. Have you checked out “Do good as you go” and The Muskoka Foundation? They are a great non-profit started by overlanders. I highly recommend them.
If you come up to Fairbanks send me a note, you are more than welcome to park in my driveway for as long as you care to.
We weren’t actually, but I’m familiar with the event and used to work across from the airfield (Bethany). There’s a few of these roaming around now and their popularity is building. Hope you do run across ours soon!
Did you guys happen to be at Airventure in Oshkosh, WI this year? There was a rig parked right by us that looked very much like yours. I spent some time admiring it but did not get a picture and never ran across the owners.
We haven’t yet but have heard it’s not bad. We have Good Sam roadside assistance so hopefully we won’t have to deal with it. With 6 tires, we shouldn’t run into a problem that we cannot wait to fix at the shop. CTIS is pretty basic. We can easily get all that checked when we are at a CAT repair location anywhere in the world. Take care!
Great looking vehicle and nice video! Had a couple of questions, have you had to change out a tire on the road yet? How difficult do you think it would be considering weight of tire. What is the maintenance requirements on the Central Air System?
Thanks and happy travels
?
Another admirer in Portland who stared endlessly while you were parked on Ash St. Thanks for the opportunity to travel vicariously with you!
Thanks for sharing – enjoyed those lyrics. Loving PDX, especially being able to bike everywhere. Not a bad place to visit for sure :).
It’s a multi-fuel engine so we didn’t have to have that discussion, it’s part of the M1083. That’s a good question about the interior of the cab. We left it fairly unmodified and kept the original look and feel of the military chassis, but got rid of the gun turet, added more sound dampening, etc. We don’t really have any photos of that currently but will very soon when our YouTube video goes live. Look for the link here or on our Facebook page in the next couple of weeks.
Just curious if you had any discussion regarding going biodiesel with GXV? Also have you posted any photos of the interior of the cab anywhere? Just curious to see how they finished it out.
So weird…I live in Portland and just saw your monsterous RV parked in front of a friend’s house. At first, I thought maybe Halliburton came to abduct our friends…Later found out about your site/story! Freaky. You two have the right idea!! Hope to do the same someday. Good luck and enjoy Portland, it’s awesome here! (not cheap, but beautiful) My website is my music website..There’s a song titled “You Rode”, which you may relate to. Take care-eel
Ariel, it’s surprisingly easy to drive and has an excellent turning radius — we can even make a U-turn :). The air brakes take some getting used to, and of course it’s heavy, so we allow extra time for braking but otherwise it’s quite nimble. We generally cruise at 55 for best mpg (around 7), but she will go 65 no problem. Thanks!
Hi. Is it hard to drive? what is your cruising highway speed?
thanks very nice rig
I spotted your rig in Bayfield WI in August. It certainly caught my eye. Good luck with your travels.
Thank you! You may inquire about pricing with GXV (globalxvehicles.com), as there is really quite a range on these things depending on preferences and budget. That said, it’s comparable to what one may spend on a nice home. (And since it is our home we could justify the expense quite easily). You’re right! We hadn’t spent much time in ABQ or NM before but it is indeed beautiful. Search for the “Goal Zero Heros” article here on the blog – there’s a pretty detailed description of what we do and why we hang out in Costco parking lots for 10-day stints :). Thanks for writing!
Such an awesome rig! May I inquire as to how much this cost? Also,why are you parked at Costco!? So many awesome, beautifully places to see here in NM.
Cool! Nope on both counts because RVs are exempt and not considered commercial.
We saw y’all, last weekend, at the Costco in Albuquerque. Was wondering if y’all need a CDL license to drive that rig? Also wondering if you are required to stop at port of entry as you cross state lines?
Thank you so much! 🙂 In fact, there was – Since this is a military multi-fuel engine, it can burn biodiesel, kerosene, NAFTA, heating oil, JP-7, etc.
I am insanely jealous, this is beautiful. Was there any discussion into making it a biodiesel?
Mike, good question — yes, the truck is surplus. GXV did all the upfit work on the cabin as well as the truck. They locally outsource a few things like paint, but otherwise they are set up to make these from start to finish.
You got a new Subie?? Yay you! Of course! You’ll be our first stop when we trek back east. What will the neighbors think when we driveway crash at your place now?
Fantastic looking expedition vehicle!! Thanks for sharing the details and really enjoy following your adventures. The interior space is well thought out and the storage garage looks about perfect!
Best of luck to you.
Did you guys buy the truck surplus? And if so who brought it to camper standards, paint ,seats etc. GXV?
Looks awesome! 🙂 Can’t wait for you to come visit and let me check it out! 🙂
I’ll let you drive my new Subaru if you let me take the truck for a spin! 🙂
Thanks so much Ryan! We would love to link up – planning to be back in the Hood late September. 🙂
Wow! Great looking rig. Definitely a little bigger than what I had in mind and I think you guys made a good choice. I look forward to seeing it in person if you are still planning to get to Hood River- you’d better hurry if you want to catch the wind!
Thanks for all your hard work – GXV is lucky to have you. Text Martin your contact info; he’d love to keep in touch.
Unfortunately no surround sound. About the only sound we can hear is the truck itself, lol. But we do have a little Bose wireless speaker we use for movies and podcasts :).
WOW !!! home away from home with all the space you need do we have surround sound as well ?
Good to hear you are enjoying the truck. I enjoyed working on it at meeting u.
Thanks, Wayne! You’re correct in that it is hinged at the bottom. Since it still drops below parallel to 23″ off the ground, loading and unloading isn’t too difficult. Our bikes are the heaviest things in there besides the tire, and we have a Little Giant step ladder to assist. As for the tire, it’s gravity-assist — just roll that baby right out the back :). Easy breezy.
The inverter is an Outback 2,500 watt. Thanks for following & hope to see you on the road someday!
Congratulations on your new home. I think it is fantastic, and hope to get my own someday. I did have a couple of questions though. As I understand it, the rear cargo area door is hinged at the bottom, rather than a lift . With that, how will you manage the weight of the spare tire and rim or any other heavy gear you’ve got? Is there another secondary winch for loading/unloading? I am picturing the patio deck as near equivalent to loading into a pickup bed, only a bit higher albeit with the added benefit of pivoting below horizontal, but limited in still staying 23″ off the ground. Also, what size inverter did you get in your rig?
Thanks again for sharing and I look forward to reading all about your future adventures!
Thanks,
-Wayne
Thanks so much! There are kites hiding in there :). And we stowed the board up on the roof rack. The interior storage there is very well insulated and should keep the temp reasonable for the kites. The inflatables depend on what you plan to use them for. In general, starboard, red paddle, hala are great, but always spring for the best psi rating for the type of paddling you plan to do. Will be in the PNW this fall and hoping to do some kiting in the gorge very soon :). Thanks again!
Hey Martin! I LOVE LOVE LOVE the new rig. That’s coming from a fan who loved loved loved Vandal. Anyway, I have a few questions for you. I didn’t see any kites in the garage. Are you still kiting? Have you ever had to worry about heat in the vehicle where you store your kites? That’s always been a huge concern of mine. You mentioned inflatable paddle boards. I was just wondering what brand you like and if there are any you think one should avoid?
Thanks for this, very in-depth, interesting to see the “garage” and know what your MPG are working out to.
Looking forward to following your adventures.