Project "Autonomous" F-350


I'm kinda fretting the dually thing. Obviously nothing handles heavy loads like dual wheels....but duallies suck in mud. However, if I already had a nice factory dually rear end laying around.........I know what I'd do.
The downside to the dually is the amount of money I have invested in my Trailready beadlocks. I have a bunch of Falken Wildpeaks too. I did not plan on running anything different. I have to put on my thinking cap and come up with some super light construction techniques. That will help my offroad ability too.


If it wasn't for the weight you could slip a set of spacers between the rear duals and keep the tires and buy two more. Of course that doesn't re-use your wheels. I love the spaced out- fat tire duallies I see now- but dang they are WIDE!!!! It'd be hard to get in any narrow places with a track that wide. I was considering doing the big tire thing with my work truck re-model....but I think I'm going with 265's, maybe 255-85's. I've decided weight handling is more important than off-road prowess for that truck. You definitely got your hands full figuring out what to do. But, you've done a great job every step of the way- I'm sure you'll continue to do so. Good luck.
I wouldn't run duals. They weigh a lot, aren't the best performance-wise, are cumbersome and you lose the beadlocks. Go with a load E rated tire and you should be good to go.


My two cents....
I think it's a no brainer that you should run a dually axle, the box is wide and you'll want the stability of a wider track width. I don't know about yours but my 37x12.5s are rated at 3970lbs. I think there's a good chance you can get away with singles, but run them on the wider dually axle.


I think it's a no brainer that you should run a dually axle, the box is wide and you'll want the stability of a wider track width. I don't know about yours but my 37x12.5s are rated at 3970lbs. I think there's a good chance you can get away with singles, but run them on the wider dually axle.
Agreed, on all counts. Not only will the DRW axle widen your track by 7", it is also stronger in that it uses tubes with thicker walls. The brake shoes are also wider, with larger wheel cylinders.

And with single wheels on a wider axle, you can also run larger outboard air bellows if you so choose. Or you can move the shocks outboard of the frame rails, this alone will make a huge difference in handling. Or you can do both of these :D


I am finalizing my fuel delivery system design so I can work on fitting the box to the frame. I want to ditch the in-tank fuel pumps in the name of "I don't want to be stranded when a pump goes out." I am going with pumps and 10 micron filters from AEM It will be a redundant system with two pumps. I am also looking for a fuel/water separator. I had to find something that was as nice as my Drake Offroad fuel fillers, lol. The only thing left is to decide whether I want to run a pair of fuel cells or a custom large capacity tank. I did not know it was so hard to find a large tank for a gas powered truck. There are plenty of diesel tanks for sale but EPA regulations make it too expensive to certify anything for gasoline. I am waiting for a quote on a custom fabbed tank before making my choice. I will be mounting the tank or tanks behind the rear axle. Since I am extending the rear of the frame to match the length of the box, I have room for a long tank there. All of the camper components will be mounted towards the front of the box which falls between the axles. :chef:

Drake fuel filler door

AEM external pump

AEM inline filter




I have read your thread but I do not recall if you put anything where the spare tire used to go. On my 97 CCLB 7.3 I have two tanks, the forward one is 18 and the rear is 16. Like you I want a bit more fuel capacity and just picked up an Excursion 44 gallon tank which will fit in the rear location and when installed will not stick down any further than the OEM tank and spare tire combo did. For me adding that weight behind the axle is not ideal but everything is a trade off, at least it is poly so I wont have the flaking issues like Fords current steel tanks and it has its own skid plate / cradle. There are some that have installed the SD front tank but for me this one sticks down to low and on a long wheel base truck you loose a lot of breakover clearance. I realize this still has an internal fuel pump in the petrol form but if you found a diesel tank it will just have the siphon tube and that should work for your external electric setup just like the external electric setup the diesel Excursion uses.

The others that have done this have kept the twin tank setup and had no issues with the transfer switch. Also, that once the wires are spliced for the fuel level guage or plugs are swapped that the dash gauge reads correct, it appears ford uses the same ohms for a lot of their sender units and dash pods. Its too cold to put mine in now so its slated for warmer weather, but there are a bunch of others who have swapped tanks in an OBS. I know, not an OBS This 38 gallon tank is more popular as is the 33 gallon from a Bronco

I will keep looking for the OBS/Excursion swap, my google **** is lacking this morning.

If you see my guys, tell them I said hello. No Baja this year, I am going to AK on the bike this summer.

Cheers, Chris


I am looking into having a custom tank built. It will run down the center of the frame rails from just behind the cab to the rear of the truck. The dimensions are 96 long, 24 wide and 7 inches tall. That is around 64 gallons. Yes, I realize it will be close to 400 pounds when full, but I won't be running with a full tank all the time. I spent this morning sourcing a fuel/water separator that flows enough to keep my AEM fuel pump happy. I might need a three point mount for my tank. :yikes:


I was thinking aluminum for the tank but eventually went with a poly boat tank. I was concerned about frame flex over such a span. If it will tear up a camper box, don't want it twisting the fuel tank either. I'm going to run it centered between the frame rails. I will have to modify the x-members but I will do that while incorporating the tank mounts. BTW, it's a 60 gallon tank. :snorkel:

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Expedition Leader
using something akin to the rubberized exhaust hangers for your tank. Still a strap or tray mount, but suspended such that frame flex is a non-issue. But that is counterintuitive to off-road driving, washboarded roads etc. And a full gas tank weighs a hell of a lot more than an exhaust system. Or configure a tank that runs predominantly in a crosswise direction to frame twist is less of an issue, or two smaller tanks side by side independently mounted, either plumbing both fully or using one as a transfer tank.

As for the 'granite' lol, there's lots of attractive laminates available now, or even a 1/2" thick Corian(?) counter that will give you 90% the look of granite at far less than granite weight. Use 1/4" alum plate veneered with laminate. Rigid enough, weighing a tenth? of stone. Think 'veneers' for just about everything. Thin and light, you can have as 'rich' an interior as you want for little weight and lost interior room, and at a moderate cost. I'd be happy to mail you a couple of my scrap bits of the PSA Oak veneer I refinished my kitchen cabinets with, for your inspection / consideration. The stuff is about 1/16" thick and took stain and finishing like a champ and is stuck on like krazy glue.

(I made the 35 cab door and drawer fronts from scratch too, took a while later to get it all done)

Anyway, my point is you can do a lot with veneers and have it look real nice.

How's your overall layout coming, have any overall pics or finalized design sketches? I've lost my grasp of your overall layout. You still wall-mounting things and having them fold down into place for use? IIRC you mentioned bike stowage? can the bike hang from teh ceiling without impeding other things? What's your shower / sanitary setup, gray / waste tanks? small ones?
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You're going to want some serious baffling in that tank to not have issues with slosh and exposing the fuel pump. Also I would compress the driveline to full stuff and make sure it's not going to interfere with the tank anywhere. You may consider running a surge tank as well, to keep the engine from starving of fuel in off camber or steep situations.

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