Van-up 9-passenger 5th wheel hauler based on Chevy Express 4500 Cutaway

[Artem]

This thread is about the potential project that I have been thinking of a lot lately.

We're a family with 2 little kids and our current set up is this:


We have been fulltiming for the last year and often traveling overseas. It's a Savana 3500 155" wheelbase van (15 pass. with 5 row seating) with 6.0 liter gas towing a 39' TT.
We very much like lots of room that we have in our van, as we use it as our main family vehicle. Picnics, toys, potties, bicycles - not a problem.
But we also like 5th wheels for their homelikeness, lots of ceiling room and better towing.

What I envision is a unique "van-up" built by combining a 4500 cutaway 159" wheelbase dually chassis with cut body of a window van and dually pick-up bed.
The body will be cut right behind the 3rd row seat, allowing to seat up to 9 passengers inside. Or have the 2nd row removed, carry up to 6 people and get 4ft of legroom between the seats - great for long trips. Or drop a power sofa in the rear and have a sleeper cab.

It must be a 6.6 Duramax diesel with a 4L80E or 6L90E (depending on the year) as Allison transmission is not available. Our current 6.0 gasser was slow towing our 10k lbs TT in California hills and was overheating.

The end result will look something like this:

Pick-up bed will have to be installed. There's a company that sells fiberglass cap backs for $500 (such as cabbacks.com).

Known issues:

1) What is core VIN - frame or tub? I have access to insurance car auctions and want to get a lightly used dually 4500 with duramax and cosmetic front damage. Throw away the cab, use the frame. I will also need a damaged in the rear window van (short or long) to cut. I want the final result to have clear title on it. We're in California if that matters, can travel.

2) GCWR for 159" 4500 is 20,000 lbs. Curb weight for cutaway is 5,000 lbs - when I add half body, seats, stuff and people will be 7,000 lbs.
Max payload is 9,100 lbs. Trailer rating is not defined for cutaways at all. (Official GM spec sheet says N/A)
How much of a 5th wheel RV can I legally carry? Since no 5th wheel will have 9,100 tongue weight, can I carry anything?

3) Cutaway WB is 159" and 15 pass. is 155". This 4" difference won't allow me to use the entire van body, so I will have to invest lots more work and $ by having to cut body and install dually bed.

The end result is a ultimate 5th wheel tow vehicle for large fulltiming families - and we have met quiet a few of them.
No work has been done yet - only internet research. Your opinions?

[gggplaya]

Why not just get a motorhome and fix that up??? Then just tow a minivan or a jeep or something behind it??

Plenty of motorhomes out there with rear bedrooms, you can customize it with bunks and fold out couches and stuff. This place has plenty of things like that you need for a custom RV. Sprinter Seats,Intergrated Captains Chairs,Sofa Beds,sedonaI


Or you can buy a used school bus for super, super cheap and convert it to a motorhome if you really want a project. There are actually plenty of cheap low mileage school buses out there at auction. No one seems to want them.

[wingnut60]

This is possibly a great project--hopefully, you will be able to set it in motion and document the process for the rest of us.
If the payload if 9100 and the as-built weight is going to be 7000, then the pin weight will be limited to 2100 lbs, which will max the gross weight of a fifth wheel at somewhere around 10500--not enough fiver for your needs, I wouldn't think. You are going to have to upgrade the undercarriage or ignore the GVWR and go with the rear axle capacity from the mfg (axles are usually rated higher than GM will rate the installation) or accept the carrying capacity of the 4 rear tires as the max rear axle weight.
Also, from the pic you photoshopped, you may have a problem even with a slider hitch.
And forget about 'legal' weights--I don't think there is anyway you can do what you are thinking about and come out with everything within the original ratings--and still have enough room in the fiver for what you need.
Can't wait for further developments...
Joe

[Scarab0088]

Is a great Idea! Was all the rage in the past. "Centurion", a company in White Pigeon, MI did thousands of them with Fords.



The VIN selection on a modified vehicle project would usually be mandated by State Law, like in CA the VIN is usually derived from the body tub (firewall) and not the chassis or running gear. Your local Hot-Rod guys will know all about these State laws...just visit a local performance shop.

Best luck

[SmokeyWren]

Lots of ways to skin a cat. Your way would be a major project requiring lots of sheet metal work and painting, after you found the right wrecks in the junk yards. Then you would be restricted as to how big a 5er you could tow without exceeding the GVWR of the GM van. And your cab would be much smaller than you're thinking. The 5er hitch must be installed in front of the rear axle of the van, or at the most dead center over the rear axle. Then you need a minimum of 36" between the center of the rear axle and the back of the cab, along with an expensive SuperGlide hitch that weighs 300 pounds. Else you can have disastrous contact between the front of the 5er and the rear of the cab during tight turns, and especially when backing the trailer into a near jackknife.

The normal 5er toter is a pickup with an 8' bed that has 54" from the center of the axle to the back of the cab. With that setup, you don't need a slider hitch such as the SuperGlide. But if you design your van to have 54" between the center of the rear axle and the back of the cab, that wouldn't leave much of a cab. So figure on 36" and a slider hitch instead.

There have been commercial conversions of cutaway vans into 5er toters, and probably some of the van conversion outfits still make them. So find one and study it before you begin torching sheet metal. Here's one from "back in the day":


Another way would be to use your current van and add a Trailer Toad between the 5er and the tow vehicle. That eliminates the hitch weight problem, saves you a bunch of body work, and leaves you with the full interior of the van for rattling-around room when on the road. Your only restriction then as to 5er weight would be the GCWR of the van. If you stay below the GCWR (combined weight of wet and loaded tow vehicle and trailer) then you should have no problem with overheating anything in the drivetrain or with being the slowpoke holding up traffic on hills and mountain passes.
TrailerToad.com

Not cheap, but probably a lot less than a full custom conversion you described.

Of course one obvious choice would be a travel trailer instead of a 5er, then the van doesn't need any modifications. There are travel trailers with over 7' of headroom, and it's a myth that 5ers tow better than TTs. If you pay the big bucks for a ProPride hitch, a TT will tow just as good as any 5er. Yes, I have a 5er, and I also have a TT with a ProPride hitch. So I have first-hand experience with both. If your current van doesn't have enough GVWR to tow a big TT without overloading the tow vehicle, then the TrailerToad can be used with a TT too.

[Scarab0088]

Did you know that GM used the Chevy van for the body on the late model Kodiak/Top Kick? A cool mod could include the Kodiak front end - Van center and bed from a Dually 3500 or just cut-away the van(?). Better engine and more suspension than the 3500 van!

[Artem]

Originally Posted by wingnut60

If the payload if 9100 and the as-built weight is going to be 7000, then the pin weight will be limited to 2100 lbs

Joe, for 4500 model is 14,200, and 9,100 lbs is payload - how much stuff you can carry. Think of a regular box truck such as Uhaul or Penske.
If my curb weight would increase to 7k lbs, I would be able to carry 7,200 lbs tongue weight.

Yes I have seen all those Ford van-ups, and that is what inspired me! They rarely show up on eBay, such as Ford Other Pickups El Dorado | eBay and I saw one on a junk yard once - loved all this room inside. However, they are all over 30 years old and carburetted gas engines are way weaker. As of today, no company offers anything similar.

SmokeyWren - great comments about 36" clearance, I didn't have these numbers - thanks. The 4500 cutaways come in 159" and 177" wheelbases, this can possible be built on a 177" chassis, giving us significantly more room.

Well the other option is to get a Wildwood park model 40' TT with 4 slides and high ceilings and have no fun

[L.C.Gray]

Taken a step farther...

[dayle1]

Originally Posted by SmokeyWren

The 5er hitch must be installed in front of the rear axle of the van, or at the most dead center over the rear axle. Then you need a minimum of 36" between the center of the rear axle and the back of the cab, along with an expensive SuperGlide hitch that weighs 300 pounds. Else you can have disastrous contact between the front of the 5er and the rear of the cab during tight turns, and especially when backing the trailer into a near jackknife.

Superglide is not the only option and 36" is not the minimum distance. The Reese Revolution (aka Sidewinder) pin box moves the pivot point about 20" behind the king pin yet still keeps the pin weight over the axle. While a minimum of 48" total is needed for jack-knifing 90 degrees, it is rarely necessary, so with the Sidewinder 20" offset, a 28" clearance would certainly be sufficient. Even less would work, GM short beds have about 42" clearance, I've used them for over 25 yrs without issue. And today's notched front cap fivers work better than fivers from 25 years ago. So, a 22" clearance plus the Sidewinder's 20" offset should work ok with a notched front cap fiver. Also, there are examples of RVers using the Sidewinder or the Superglide in conjunction with today's super short bed trucks where clearance is certainly less than 30".

Maybe this link will explain it Good Sam Club Open Roads Forum: Tow Vehicles: 1/2 ton trucks?

Best I can determine, cab-to-axle distance is about 26 inches for the F150 with the 5-1/2 ft box.

[jenandjon]

Centurions were awsome.

[soundman7]

This would be my ultimate tow rig

http://cr.rvgallery.com/vehicles/p10239