Prepare for a long post with lots of van opinions:
I have a 01 7.3L E350, 4x4 on 37s, with a pop top. I tow my JK with it, camp out of it, do Home Depot runs with it, etc. I love it, and would build another if I had to replace this one. I'm not sure I'd build it exactly the same, more on that later.
It “does everything” that my 1ton JK doesn’t do, and there’s some significant overlap. I’ll take the van on a mild local wheeling trip (Hollister Hills) if I don’t feel like loading the trailer and nobody is bringing any built trucks/buggies.
I love that I always have my camper. On Rubicon/Fordyce trips I'll sleep in the van at the trailhead on the first and/or last night of the trip. On Sand Hollow trips I'll break the drive in half and camp on BLM land in the Mojave desert. With the power pop top I have camp set up in a couple minutes, without getting out of my seat, and without waking the kiddo. I'm going to JV for the first time with the pop top and kid in 6 weeks, we'll see how that goes. For mountain bike rides, I always have cold beer in the fridge for after ride, and I can put a bike inside the van and not worry about it getting stolen off the rack.
It tows plenty well for me, with about 7k behind it. I can't comment on more weight. Flat ground it'll do 75-80 no problem. I can hold 55-60 all the way to Fordyce. Here's some comparisons from my experience. We had a '16 Duramax 2500 at my last job and pulled a 28ft box trailer that weighed about 7k, and I'd say it was maybe 20% nicer to drive. A buddy's '19 6.7L PowerStroke was roughly similar to the Dmax. My buddy had a 2V V10 F350, and I'd say it was maybe 10% nicer to drive towing than my van.
I used to DD it, then got a shitbox DD. It wouldn't be any worse to DD than any similar era/spec truck. Firing up a 7.3L diesel to drive 9 minutes to work gets old.
I agree the pricing on 4x4 vans is dumb, and you pretty much have to build your own. Most of the factory converted ones are borderline junk. I used the
U-Joint Off-road conversion kit, which uses 99-04 super duty axles and leaf springs. It’s been on there for over 4 years and it has been flawless. It drives and tows better than stock, but the stock parts had 250k+ on them. I did the conversion in my driveway with a few buddies working casually, and it took 3 days, including the transmission swap and t-case install.
In the years since I did my conversion,
ExpoVans and
Colorado Campervan have also started doing 4x4 conversions, I believe both with 05+ Super Duty axles and coil springs. Neither list DIY kits on their site, but it would be worth a call.
IMO, if you want a 4x4 van and want to tow with it, a converted E350 with a 7.3L or V10 is the way to go. E250 would technically be the same, but I find most have 5.4L V8s. 6.0L PowerStroke was available, and are, well, 6.0s.
Chevy Express and Dodge Ram van require all custom work to convert, and have worse engine/trans options. You might be able to make an argument for a Duramax or 6.0L gas Express van, but they also have tiny wheel wells. The AWD Express was only offered as a 1500 with a 5.3L.
Here's some of the downsides of towing with a 4x4 E350 that I see.
Your friends will make free candy jokes for at least a decade
The E-series was released in '92, and Ford refreshed them in '97, and '08, ending production in '14, so they're all nearly 10 years old. If you want a 7.3L, it's 20 years old. You get to enjoy 10-20 years of wear and tear. You also get all the creature comforts available in what was basically a work truck 10-20 years ago. You want adaptive cruise control and heated seats, good luck. Door seals that were designed in the last quarter century, not gonna happen.
The 7.3L PowerStroke didn't get an intercooler, and there's only a few people that I've found that have done custom intercooler setups on them.
Ford never put the 3V V10 in the e-series, so even if you get a late model V10, it's got the motor they stopped putting in the trucks in '04.
They're loud. You're sitting on top of the motor in a vehicle with minimal sound deadening and 15 year old seals. I'm working on gradually improving this, but it's never gonna match what a new truck does.
In my opinion, if you’re going solid axle under an E-series, you need 6” of lift to get enough front suspension up travel for it to work well. 6" lift on 35s or 37s is tall. My wife and I are tall, and our 4 year old has figured out how to crawl in/out, so it's not an issue for me, but my my MIL couldn't get in if she needed to. Maybe that's a benefit.
The extended body is worth it for the extra room in side, but it does tow a tiny bit little worse. I had a 5.4L regular body before this one. Both length vans have the same wheelbase. The Chevy extended body has a longer wheelbase, one more point for GM.
No "dirty" cargo space like a truck. I have a tarp, a hitch mounted cargo rack, and a trailer and can usually move whatever I need with a combo of those 3. Occasionally I'll borrow my dad's beater pickup, but it's pretty rare.
If I were to do it again, I'd probably do the same thing, but I'd think hard about a few other options:
When I built it, I was riding a motorcycle most days, then driving the van if I was being too much of a bitch to ride in the rain. Since then, I had a kid, and have to pick him up from daycare every day, so I got a DD. Now the van is just used for towing/camping. I might build a short bus for that.
The 7.3L is loud and the leaf sprung solid axle isn't fast off-road. I might prefer a V10 and TTB swap it, so I have something that can eat up dirt roads better. I also might look at a 05+ Super Duty 60 coil sprung swap, but I think the real issue is up-travel.
Buying a brand new E350 cutaway with the Godzilla 7.3L gas motor for about $45k and grafting the back of a donor van onto it would be a rad project that I would love to see done, but I don't know I want to undertake it.
box is 12'2 inside. And really tall.