4x4 Duramax/Alaskan Camper Flatbed Build

[Big Greener]

I have traditionally done my "expo camping" out of the back of Toyota 4x4s (Land Cruiser, LX470, and 1st gen Tacoma). I've had a 2001 GMC Sierra 2500 HD 4x4 which we used to pull a trailer with for quite a while, and I'd been considering finding/buying and stabbing in an older used slide-in truck camper to use as a base of operations for dirt bike trips. We upgraded from our bumper-tow trailer into a 36' diesel pusher, which is great for taking the whole family along and all of the toys, but is really limiting on where we can go, so I wanted a setup that would allow for maximum accessibility.


Original use for the truck

When I started educating myself on truck campers, I quickly realized that most of the available options on the market would be too large/cumbersome to really get us into the places we like to camp--I wanted to be able to make it to mountain tops, run BDRs, etc. I was unfamiliar with the whole popup scene, but got turned on to Four Wheel Campers, and started considering going that route. The only thing I didn't really like was the soft sides--we live in the PNW and camp in the rain/snow/whatever, and so hard sides seemed like something I would want. And then I found out about Alaskan Campers... The pros of a popup, along with the pros of a hard sided camper? That seemed like it was right up my alley! Also, the company was based right near my "home town" which was awesome--I was surprised I had never heard of them before, and chalked it up to being uninformed in the space as a whole.


In the PNW (near Mt. Rainier) you just have to camp in whatever weather you get

I started shopping seriously for an Alaskan, joined all the social media groups, read up on the posts on EP, etc. Yup, an Alaskan was definitely the rig for me, but they are made in relatively smaller numbers, and so the availability on the used-market is a little scarcer than I initially anticipated. I considered going with a new unit, but after talking with Bryan at the factory, I realized a used unit was a better fit, since I could have it "right away" provided I could find one. Then, someone in a Facebook group posted a link to a 2019 Alaskan Camper flatbed model at an estate auction near Fallon, NV.


The original picture as provided by the auction--2019 Alaskan Camper

I had not considered a flatbed version, but was intrigued by the possibility--the paint on the bed of my truck was less than great (early 00's white paint isn't known for it's longevity) so ditching the janky paint for a flatbed sounded like a cool plan! I got my wife's buy-in for the concept, and then started doing some research on this particular camper. I called the auction company, and they initially offered me minimal info on it. They were unfamiliar with any of the specs of the camper, and were also unsure if all of the systems worked. They said "it seems to be in good shape" and answered whatever other general questions they could. I then reached out to a couple of guys on the Facebook page who seemed knowledgeable, and they provided me great info on areas to check, best guess on the value of the camper, etc. The auction had a week left, so I registered, made an initial bid, and then sat back to let the process unfold.

 

[Photobug]

Following but not sure if you won the auction yet or just bid on the Unit so far.

 

[Big Greener]

I was quickly outbid, which I anticipated, so I kept an eye on the proceedings, and went about the week. On the day the auction closed, I made sure I was home and available to bid my little fingers off if the need arose--and it did! My initial "I hope I can get it for this price" number was quickly exceeded, and so I dug in and went to work with two other anonymous bidders. The action was hot and heavy, and extended the auction several different times. My heart was racing as I bid and was outbid, only to quickly bid again. As we approached my ultimate "hard ceiling" for a purchase price, I began to despair that someone on the interwebs wanted this camper more than I did. Even at the higher prices we were getting into it was still an incredible value, so I forged ahead. I hit my limit and I held my breath--that number must have been the other bidder's "magic number" as well, because the bid did not increase, and the timer slowly wound down to the auction's conclusion. I won! I was pumped, and made immediate contact with the auction and the estate's executor to finalize payment and pickup timelines. I also started to think about what the heck I was doing--I was the proud new owner of a flatbed camper, but did not own a flatbed truck... Now what?


I bought a janky old flatbed of Craigslist, of course!

What I quickly realized was that I had essentially "put the cart before the horse" (as I'm pretty prone to do) and that I needed a plan get the camper home to Washington State QUICKLY. The camper wouldn't fit on my car trailer (too wide) and I had no flatbed truck. After considering all of my options, I hatched a plan to buy an old beat up flatbed off of a medium duty truck, crib it to fit and strap it down to the deck of the car trailer, thereby creating a "deckover-ish" trailer I could use to get the camper home. I conned my son and two of my friends into making a late night run in the dark to buy the flatbed several hours away. It was an adventure, but we got it done! A few days later the wife and I loaded the dog into our Suburban, hooked up the trailer, and headed south! We ran into snow going over Willamette Pass on Hwy 58, but overall the trip was great!


Getting ready to load the camper


Mounted up, heading home!


There she sat while the work on the truck started

 

[ripperj]

That looks to be in great shape(at least from New England )
No windows in the cabover is weird! Be good from an insulation perspective
Post up inside pics!


Sent from my iPhone using Tapatalk Pro

 

[Big Greener]

Now I owned a flatbed camper, but no flatbed truck--time to fix that! I did a ton of research on flatbed mounted camper systems on EP and other sites, and started penciling out some basic plans. My sons and I removed the old bed, prepped the frame, and started laying out our steel.


Off with the old bed


Frame prep. I used HDPE cutting boards from Walmart to act as bushings/bumpers between the frame of the truck, and the rails of the flatbed.


My shop isn't big enough (but then no one's is). The frame was laid out on the floor initially, and then put on the lift for final weld up.


First mockup of one of the spring mounts between the truck and the flatbed.

The initial layout of the flatbed took a long time--measuring, cutting steel, laying out again, checking for square, tacking, rechecking for square, cutting another piece, etc. was tedious, but I knew I was only going to get one shot to make this thing, so chose to take my time and get it right. I worked on it in the evenings after work, and here and there on weekends. It was a great project to work on my welding, and to get my kids some more welding time too--the more beads you lay, the better welder you become! The unfortunate thing was that the project took up most of the space in my "working bay" of my shop, so there were several times where I'd have to load the half-finished bed onto the truck, cover it with a tarp, and move the whole thing out into my driveway so I could work on other projects.


Working on truck/bed alignment. Lots of pulling tape at various places, checking, rechecking, etc. Also used the old "eyechrometer" a lot to ensure things looked right along the way.


All work and no snow camping make Jack a dull boy, so we spent plenty of weekends getting the aforementioned Toyota 4x4s stuck in various locations


Time to pull cable!

 

[OffToTheSide]

Great build! Your new to you Alaskan looks like a 6.5 Cabover, or is it an 8’?

 

[Big Greener]

Great build! Your new to you Alaskan looks like a 6.5 Cabover, or is it an 8’?

It's an 8 footer

 

[OffToTheSide]

Really nice. Are you redecking the flatbed in wood or skinning it in steel?

 

[Big Greener]

That looks to be in great shape(at least from New England )
No windows in the cabover is weird! Be good from an insulation perspective
Post up inside pics!


Sent from my iPhone using Tapatalk Pro

The lack of windows in the cabover section is a bit of an oddity. The previous owner ordered it that way, along with no roof vents, extra lights in the ceiling, no water tank, no dinette, etc. We wound up having to customize it pretty extensively to meet our needs, but it was a fun process!

 

[Big Greener]

Once the deck portion of the flatbed build was done, I moved on to adding some storage. One of the benefits of the flatbed camper is the additional inside storage this design offers (in a regular slide in truck camper, the bed rails literally "cut in" on the amount of interior cabinets you can have). Based on this, I decided not to include traditional "under bed boxes" like you see on many flatbed designs, and instead focus on a storage solution for something you can never have too much of; fuel!


View of the fuel storage "cubby" on the left of the image. Also messed around with the idea of adding a pull-out storage case near the back of the bed.

I also had to determine how to finish the rear of the bed, and copied the look from a couple of other flatbed designs I had seen. I wanted to maximize rearward clearance as well, and this style seemed to allow for that.


I used 11 gauge sheet for the fuel cubbies and the rear skin.

I used LED lights, and got them all cut/fit etc. I was able to repurpose most of the wiring loom from the old truck bed to make the lighting connections as "factory" as possible. Sorry for the license plate doodle, it's lame I know...


Taking shape!

For decking material, I was on the hunt for something lightweight, rigid, and completely synthetic. Wood was too heavy/thick and prone to rot, steel sheeting was too heavy, aluminum sheet was too expensive, etc. So, in what I thought was a stroke of inspiration, I used ACM (aluminum composite material) which is common in the signage industry. It is essentially thin aluminum skins sandwiching extruded polymer. The result is a material which is lighter, more rigid, and far cheaper than going with a full aluminum sheet. It's pretty incredible stuff, and I was able to source it locally. Because the weight of the camper rests on the rails and crossmembers of the flatbed deck, the ACM really just acts as a "crud guard" against the bottom of the camper, so I didn't need the decking to be structural. It was really easy to work with, and looks great to boot


Test fitting different sizes of container in the cubby/modeling the decking

Once all of the steel work was done (lots of welding, grinding, sanding, etc.) I moved on to paint! I used an automotive primer, and then color matched the "Olympic White" color of the 2001 GMC truck for a color coat, before hitting it with a mid-gloss clear. The painting portion took a long time as well, but the finish came out quite nice.


Color match came out pretty good

Before I finalized the mounting of the flatbed and decking, I wrapped up the lighting and wiring. I also drilled into the truck's fuel tank to add a standpipe for the diesel heater I would be adding. For those who don't know, the traditional "Chinese diesel heaters" which are so common in van-life builds require a 12V piston style fuel pump which can be loud and annoying (think a jarring "tick, tick, tick, tick" for as long as the unit is running). In order to minimize the noise, I mounted the fuel pump outside, underneath the flatbed. I created a "z mount" which I screwed into one of the bed's crossmembers, and isolated the steel using foam tape (both of which dampen vibration--the z bracket allows for a small amount of flex to occur, which helps cut down on noise translation through hard-surfaces). Then I mounted an ammo can to the z bracket, and wrapped the fuel pump in insulation material. Even with the fuel pump and full chat, you cannot hear it from inside the camper, and it's barely noticeable even outside.


Fuel pump mounting solution. I also added rear airbags, and installed new Bilstein 5100 shocks on all four corners.

Once all of the flatbed related work was complete, it was time to get married! I hooked the truck up to the trailer, and drove to my friend's house who has a much larger shop in order to get the camper mounted onto the flatbed. I also extended the hitch setup in order to accommodate for the longer flatbed, but apparently I forgot to take any pictures of that...


Ready for mounting!

 

[Big Greener]

Really nice. Are you redecking the flatbed in wood or skinning it in steel?

I decked using aluminum composite material--light, strong, and affordable!

 

[OffToTheSide]

That bed came out fantastic, great fabricarion work. It seems like it was a very inexpensive price point all in for materials, too. Well done sir!

 

[Big Greener]

That bed came out fantastic, great fabricarion work. It seems like it was a very inexpensive price point all in for materials, too. Well done sir!

Thank you! I am pretty pleased with the way it turned out--it was a lot of work, but worth it! Also, as far as total cost for the bed, it was well under $1,000 for everything.

 

[Big Greener]

Having a two post lift at our disposal, we parked the trailer under the lift first, and used the lift to pick the camper up off the trailer. Then we pulled the trailer out, disconnected it, and sat the camper down onto the truck! Overall, pretty easy/simple! Mounted it to the flatbed by through-bolting the camper to the steel brackets I installed on the flatbed, expressly for mounting purposes. Grade 8 1/2 inch bolts in the four corners of the camper. This is how the factory mounts their flatbeds, so I figured it would work for me too!


All mounted up!


Turned out pretty good!


All loaded up to head back home!


A better look at the "deckover-ish trailer" contraption I made to get the camper home/store it on while building the flatbed.

Now that the flatbed was (mostly) done and the camper was mounted up, it was time to start working on the inside! The original owner ordered the camper in a very unique configuration--no dinette, no roof vents, no water tank, no sink, no cabover windows, no heater...


How the interior looked when we bought the camper. Pretty spartan...


The camper came with six huge/heavy deep cycle batteries. Apparently the original owner use the camper as a "mobile HAM radio setup." The wiring left a bit to be desired...


After some light demo/cleanup


Thinking about water tank placement...

 

[Big Greener]

The old/heavy lead acid batteries had to go! After doing a ton of research on lithium, I wound up going with two Chins LiFePO4 200 amp hour batteries, sourced from Amazon. I relied pretty heavily on reviews from Will Prowse and his YouTube channel when deciding which batteries to purchase, as well as how to design the electrical system as a whole. If you're unfamiliar with camper electricals, batteries, solar panels, etc. I recommend you check him out! For charging I opted for a Renogy DCC50S DC/DC charger. This allows for the alternator to charge the batteries while the truck is driving, and also provides for solar panel input all in the same small package.

I used resettable breakers for all of the systems, and opted for a 2000W Renogy inverter to get my 120 AC when needed. I insulated my batteries in order to keep them warm, as I will be using them in cold weather situations, and still want to be able to charge them safely. I also installed my "Chinese diesel heater" in the same compartment, so I could heat the batteries up if things ever got "too cold."


I made all of my own cables, which was a lot of work--definitely recommend a hydraulic cable crimper if you decide to go that route. Also started to frame in for the dinette at this point.


The Chins batteries weigh a fraction of the lead acid batteries, take up less space, and provide far more capacity.

On the other side of "the aisle" from the electrical center I installed my water tank. 26 gallons seemed like a great option which should allow us to boon dock for a long time. I also have the ability to replace one of the fuel cans on the outside of the truck with 7.5 gallons of water, depending on the type/length of trip we're on.


I insulated the water tank as well. I made the hold downs out of 5/8ths all-thread lagged into the floor of the camper, as I did not want that load shifting under any circumstances.


Once I started to frame up and then skin for the dinette, access got a little tighter. I sent one of the kids in there, as he was a better fit You can see the Lagun table mount as well.

I designed a dinette for seating which would also "fold down" in to another place to sleep. Once I had the bench tops and backs built, I was able to order the custom slip covers for the cushions. We used a company/website called Coversandall.com for the slip cover portion, and then cut our own high-density upholstery foam into shape--we ordered the foam from Home Depot. Once we did a "dry fit" of the foam to verify functionality, we wrapped the foam in numerous layers of cotton batting material to "fill out" the cushions.


Starting to take shape. You can also see the step I built to make getting into the bed easier. It also makes sitting at the dinette more comfortable, as well as adds more storage.


What an improvement! The dinette and the bed it folds into are both very comfortable. You can also see the vent for the heater, just to the left of the step. I also installed the 12V water pump under the step, and it fits great!