E350 Cutaway 4x4 w/ DIY Pop-Top Composite Camper Box (Build Thread)

[fjefman]

I had no luck with any dealers, none of them had any or could order one anytime soon. It was also very difficult to search for them and specific one without a box, not to mention most of them were larger and duallys. I think you may have better luck trying to find the 158 Dually you're looking for.

I ended up lucking out because @UjointoffroadCO let me know of one that was sitting on a dealership in Florida and grabbed it right away!

Yeah, tell me about it...I see lots for sale with the box but those add $20-$30K to the price and reselling them I suspect will be difficult and I won't be able to get anywhere near that money back out of it. The 450 DRW 158 does seem to be pretty common...I want that version as my needs are very different from yours. I want the capacity to load ~800lbs of motorcycles on a custom rear rack. I'm a park and play guy...need my rig to delivery me and my bikes to cool riding areas then I park it for a few days and go Moto. Plus, I want a bigger box as I plan to spend a lot of time with it and the size will be much appreciated from my current RB E-350 van.

I did find a couple more "commercial dealers" around the Atlanta area and I plan to visit them soon.

How did you get your Chassis home from FL? As I understand it they are not drivable off the lot. But I suspect a wood back with flatbed and 4x4 bumper would make it look road-worthy enough, right?

 

[fjefman]

One other question (For now). How high are you anticipating the camper floor will be over the hight of the cab floor?

In this post it looks like your subframe is even with the cab floor - https://expeditionportal.com/forum/...e-camper-box-build-thread.241475/post-3147625

So the habitat floor will be higher by the thickness of the floor panel you are using?

Related, how much higher is the top edge of your subframe over the hump of the frame by the R axle?

 

[PathNotTaken]

Yeah, tell me about it...I see lots for sale with the box but those add $20-$30K to the price and reselling them I suspect will be difficult and I won't be able to get anywhere near that money back out of it. The 450 DRW 158 does seem to be pretty common...I want that version as my needs are very different from yours. I want the capacity to load ~800lbs of motorcycles on a custom rear rack. I'm a park and play guy...need my rig to delivery me and my bikes to cool riding areas then I park it for a few days and go Moto. Plus, I want a bigger box as I plan to spend a lot of time with it and the size will be much appreciated from my current RB E-350 van.

I did find a couple more "commercial dealers" around the Atlanta area and I plan to visit them soon.

How did you get your Chassis home from FL? As I understand it they are not drivable off the lot. But I suspect a wood back with flatbed and 4x4 bumper would make it look road-worthy enough, right?

Seems like the 450 DRW 158 is a good fit for your use case! Only thing I will say, is if you are comparing the amount of space to your RB, my van has the exact same length (and overall width) as an RB e350 but I've been inside both and its amazing how much larger the inside is with the straight walls! (and slightly taller)

We were running the logistics of getting one with a box and selling it, but I don't think you would much luck getting your $ back as you said.

For transportation, we had it shipped. It was ~$1600 total. They are drivable off the lot, but you would definitely need to mount a license plate, rear lights, and fix the gas filler neck better. Even then I really wouldn't recommend driving it like this long distances, I think you'd be better of shipping it. We drove it ~20 miles to get it weighed but haven't moved it since other than around the block.

 

[PathNotTaken]

One other question (For now). How high are you anticipating the camper floor will be over the hight of the cab floor?

In this post it looks like your subframe is even with the cab floor - https://expeditionportal.com/forum/...e-camper-box-build-thread.241475/post-3147625

So the habitat floor will be higher by the thickness of the floor panel you are using?

Related, how much higher is the top edge of your subframe over the hump of the frame by the R axle?

In the photos you see, the subframe was mounted using 3d printed body mounts that I used during construction just to make things easier. The subframe ended up nearly exactly even with the cab floor with the actual mounts, so yes the habitat floor is the thickness of the floor(1.625in) + glue(~.07in) taller than the cab sheet metal. we cut this at a 45 degree angle so it makes a smooth taper into the cab. It turned out really good. We still need to add a trim piece to finish it up, but going to wait on those to do them all at once and get them powder coated. The cab also has a rubber floor and thick carpet underneath, so it only ends up being about 1in taller. it's barely noticeable!

The top edge of the subframe is about 1in taller than the rear hump. This was only possible because the long longitudinal 2in tall subframe bars run in a different plane (wider) than the vehicle frame. This is the (calculated) bare minimum to not make contact when the body mounts compress. None of this has any road miles on it so can't confirm if this is enough or not, but I think it will be fine. The goal with this camper was to keep the height to an absolute minimum: as short as possible with room for me to sit up straight on a bench seat with the top down. I really didn't want to add any extra height here!

 

[fjefman]

Seems like the 450 DRW 158 is a good fit for your use case! Only thing I will say, is if you are comparing the amount of space to your RB, my van has the exact same length (and overall width) as an RB e350 but I've been inside both and its amazing how much larger the inside is with the straight walls! (and slightly taller)
------

For transportation, we had it shipped. It was ~$1600 total. They are drivable off the lot, but you would definitely need to mount a license plate, rear lights, and fix the gas filler neck better. Even then I really wouldn't recommend driving it like this long distances, I think you'd be better of shipping it. We drove it ~20 miles to get it weighed but haven't moved it since other than around the block.

Yeah, building my current RB, with its egg shape was a pain and with a high top it is even worse...the width at the top is about 24" narrower than that at my knees. So looking forward to a square body...well until I take it off-road that is. ;-)

Re: just the chassis...you were able to get it insured and tagged right off the lot? If so, that is encouraging...I was told that was difficult...but not by anyone who has ever tried it.

 

[fjefman]

In the photos you see, the subframe was mounted using 3d printed body mounts that I used during construction just to make things easier. The subframe ended up nearly exactly even with the cab floor with the actual mounts, so yes the habitat floor is the thickness of the floor(1.625in) + glue(~.07in) taller than the cab sheet metal. we cut this at a 45 degree angle so it makes a smooth taper into the cab.

Awesome. Yeah, for my RB van I just put tome EZ cool under the front carpet and then 1" foam board, 1/4" snap-together wood flooring and then a sheet of vinyl on top of all of that. The hight difference is a non-issue. I've climbed in and under a couple dozen Class C RVs at this stage and am always shocked at the 6-8" hight difference between cab floor and box floor...but those are built for a low cost, nothing else.

The top edge of the subframe is about 1in taller than the rear hump. This was only possible because the long longitudinal 2in tall subframe bars run in a different plane (wider) than the vehicle frame. This is the (calculated) bare minimum to not make contact when the body mounts compress. None of this has any road miles on it so can't confirm if this is enough or not, but I think it will be fine. The goal with this camper was to keep the height to an absolute minimum: as short as possible with room for me to sit up straight on a bench seat with the top down. I really didn't want to add any extra height here!

Yeah, I was planning on the same...but are you sure that 1" is still needed? I mean do body mounts compress that much?

Wait one...

OK, I just went and crawled under my van and the body itself is 7/8" above the highest point of the hump. FYI, in front of the hump is the shock crossbeam and behind it is a body x-beam so Ford did the same thing...running the body beams "around" the humps.

I don't know how much the mounts have compressed, but your 1" now makes perfect sense...and it explains how Ford can get a flat floor front to rear with a single piece of ribbed sheetmetal, but everything in the aftermarket is going to have taller rear floor.

I'm planning to tackle my overall hight issue a little differently. I want 6'6" interior height (I'm 6'4") and on the roof the Maxxfan will be the tallest thing up there so I'm actually considering only doing a 4" suspension lift and running essentially 33" tires. She will be tall...I've not figured out how tall yet, but I'm thinking 10' 6". No where near as off-road capable as what you are building but that is OK for me and my park and play usage.

 

[fjefman]

For reference, this is how I’ve been traveling on some big trips…she has been off-road plenty, but mostly just forest service roads and minor offshoots of them. Only grounded the rear rack a couple times, and only used the rear locker in real life twice..both times leaving a wet grassy field. I say real life as I almost always use it when getting the van up on leveling blocks when parking.

She is a 2wd van with the ARB locker installed by U-Joint and a the 3" Ocotillo Cruiser long-radius-arm lift kit from Weldtec.

 

[PathNotTaken]

Awesome. Yeah, for my RB van I just put tome EZ cool under the front carpet and then 1" foam board, 1/4" snap-together wood flooring and then a sheet of vinyl on top of all of that. The hight difference is a non-issue. I've climbed in and under a couple dozen Class C RVs at this stage and am always shocked at the 6-8" hight difference between cab floor and box floor...but those are built for a low cost, nothing else.


Yeah, I was planning on the same...but are you sure that 1" is still needed? I mean do body mounts compress that much?

Wait one...

OK, I just went and crawled under my van and the body itself is 7/8" above the highest point of the hump. FYI, in front of the hump is the shock crossbeam and behind it is a body x-beam so Ford did the same thing...running the body beams "around" the humps.

I don't know how much the mounts have compressed, but your 1" now makes perfect sense...and it explains how Ford can get a flat floor front to rear with a single piece of ribbed sheetmetal, but everything in the aftermarket is going to have taller rear floor.

I'm planning to tackle my overall hight issue a little differently. I want 6'6" interior height (I'm 6'4") and on the roof the Maxxfan will be the tallest thing up there so I'm actually considering only doing a 4" suspension lift and running essentially 33" tires. She will be tall...I've not figured out how tall yet, but I'm thinking 10' 6". No where near as off-road capable as what you are building but that is OK for me and my park and play usage.

Yep, exactly. I based my spacing on the regular body vans. Though I don't use the Ford lateral spacers, I used a polyurethane body mount puck to get the extra little bit of height. This also acts as a cushion if any frame slap occurs with the spring mounted design. As for the body mount compression, I've seen the rubber pancake pretty dang flat so I Just wanted to be careful with that.

10.5ft overall height sound very proportional to your 158WB and overall length. I'm looking at about 9ft tall with 37's and the 6in UJoint kit, but still to be finalized. I am 6'5" which made pop top a must for this height and side sleeping not possible with the width of habitat I wanted.

Also, now that I think about it the 138WB comes with 240in long of frame total FYI. I cut about 2ft or so off for my fully supported >10ft long box.

No issues getting it tagged and insured off the lot. Only hiccup has been finding affordable non commercial insurance since it's classified as commercial due to payload. Dealing with it for now until I can get it re-titled as RV.

 

[fjefman]

Good plan.

As to insurance, FWIW I had issues with my Van when I got it..it was a wheelchair can, complete with rear lift, and was a commercial vehicle when I bought it. Progressive insurance, worked with me to get it taken care of..honestly don’t remember the solution but it did take multiple calls.

The RV route is a better solution though.

 

[PathNotTaken]

Final Mounting of the Subframe + Exo:

After countless setbacks with mounting, we finally got it done. We had endless issues with the factory Ford body mounts including incorrect part numbers from Ford, inconsistent manufacturing flaws, rust, and user install error.

As I’ve already gone over, we’re using the factory Ford mounts, just adding red polyurethane pads and captured springs to assist in extra isolation of the camper from the frame. The polyurethane pads are to raise the height of the subframe and act as a cushion when the subframe separates and crashes back down (frame slap). The idea of the springs is they are only utilized when the frame rails begin flexing independently of each other, and in normal driving condition remain relatively static. There are a total of 5 mounts on each side. Installation process consisted of torquing just the Ford rubber down to 60ft-lb to set the rubber, then installing the spring and tightening until the spring was slightly compressed. Here are the lengths/springs/rate we used:

Position (referenced from back of cab)	Spring Length	Spring Rate (lb-in)	Spring Rate (kg/mm)	Total Spring Travel (in)	Lee Springs Part #	Notes
1/2	n/a	N/a		N/a	N/a	Just using the factory ford bushings here
3/4	2in	2205	39.3	.05in	LHL 1500D 01
5/6	2in	1250	22.3	0.61in	LHL 1500C 01
7/8	3in	1000	17.8	0.92in	LHL 1500C 03
9/10	3in	560	10	1.135in	LHL 1500B 03

Since these springs fit inside of the frame rails, the amount of space we have is limited, particularly towards the front. As you can see by the chart, we used increasingly less stiff and longer springs rearward. This should allow the box to stay relatively inline with the cab.

We since have about 1000 road miles (all highway/city) on it since installation and have not had any issues. The real test will be once we are more near final weight, have the 4x4 conversion, and flex it out. I'd also like to setup an action camera with a live feed so I can see how they are behaving while driving.

 

[rruff]

Great info!

 

[DoryBreaux]

Can't wait to see this one come to life. So rad!

 

[PathNotTaken]

Thought I'd share a link to our YouTube & Instagram if anyone is interested in following along on the build there.

Still planning on keeping the forum up to date, but will be using instagram for more photos and everyday building/progress, along with YouTube for long form video.

Speaking of which, first YouTube video outlining why we're building a vehicle, build considerations, and high level of the plan is up on YouTube!

Next up will be a video on the subframe design. In the meantime, we've moved into a much bigger shop space and are currently waiting for @UjointoffroadCO to complete the 4x4, so have been focusing on setting up shop but are eager to get the van back and get back to it!