Chevy van 4x4 conversion
- Thread starter jason77
- Start date
indecisivebrad
New member
Since the C4 the corvette has been a unidoby in some form or another. They started out as a body bonded to a frame, similar to the full size vans we're talking about, and then eventually transitioned to the standard unibody design. They make it a point of calling it a monocoque chassis though so people won't think of it the same as they do a Camry. When comparing an 80's vette to an 80's G series you have to take into account that a steel van welded to a truck frame isn't as weak as a plastic and fiberglass body glued to a lightweight sportscar frame.
2000's express 3500 vans--not unibody
If I had choice, I would have chosen a Ford over Chevy if offered by Roadtrek for the the 190 Popular. This is just based on many years experience doing fieldwork in Ford Trucks--Broncos and F series. The 3500 express model vans (2000's) are not unibody, but body on frame and built I think pretty similar to Ford E-series.
Not sure why folks continue to propagate the old myth of the 3500's being unibody. Newer Ford E-series are getting very hard to find, and most that I found while looking were passenger vans.
If I had choice, I would have chosen a Ford over Chevy if offered by Roadtrek for the the 190 Popular. This is just based on many years experience doing fieldwork in Ford Trucks--Broncos and F series. The 3500 express model vans (2000's) are not unibody, but body on frame and built I think pretty similar to Ford E-series.
Not sure why folks continue to propagate the old myth of the 3500's being unibody. Newer Ford E-series are getting very hard to find, and most that I found while looking were passenger vans.
justcuz
Explorer
Chevy vans had unibody long before Corvettes did, your reference is confusing. Chevy Express vans received a full separate ladder frame in 1996 and have them to this day.
Chevy vans when unibody were never steel bodies welded to a truck frame. They were stamped steel u shaped frame rails welded to the van body, not heavy channel like a truck frame.
Corvettes even today have a steel or aluminum frame structure that the body is bonded to and before the C4 had a separate frame like a truck or 1996 and newer Chevy Express full size van.
Comparing the 2 as any kind of equal as for as unibody is concerned is like apples and oranges.
Last edited:
deserteagle56
Adventurer
I've had both so some real-world experience....
I bought a new 1976 GMC Vandura "Terravan" conversion in June of 1976. 400 small block, TH350 tranny, full-time 4wd. And drove this thing all over the country but primarily the back roads of Nevada and Utah for 32 years. One of the first changes was to install a Rough Country part-time kit in the transfer case, then remove all the California smog stuff and install an Edelbrock intake and Holley carburetor which brought my fuel mileage from 8 mpg to 12 mpg. Yes, it was unit-body construction which was very rigid - no body twist at all when I had it in a twist and one front wheel and one back wheel was off the ground. But that "frame" under it was not very strong - after about 10 years of rough dirt roads I had to have reinforcing plates welded to the frame where the transfer case mount bolted up because it was cracking. I drove this thing, generally hauling a dirt bike and camping out in it, for 32 years.
In 2007 it became evident I needed to either completely rebuild this old workhorse or get something newer. I wanted a diesel for the better fuel mileage so I started doing some research and really liked what I read about the GM 3500 vans with the Duramax engine. By the way, people assume that because the GM vans can be equipped with a Duramax, they also come with the Allison tranny behind it. Not so. That tranny is too big to fit underneath the van body so the diesel GM vans get a version of the Hydramatic. I found one of the van convertors in Oregon who was at the time converting a Chevy van so I went to take a look. The guys there told me they would convert a GM van to 4x4 but only under protest. Two reasons. You ended up with a GM van with a lot of Ford parts so getting it serviced was a problem. The other was - even though the GM van was now built body on frame, the frame was not nearly as rigid as the Ford. They had a deep ditch on their lot where they could test a rig's resistant to twist when crossing that ditch at an angle, and also check on how the suspension worked. The Chevy van's frame twisted so badly that the front bumper actually made hard contact with the body of the van. The Ford van, on the other hand, did not exhibit any noticeable twist and that decided it for me. I became a Ford van man. I used to have some photos of the vans crossing that ditch but can't find them right now. This is what I have been driving since 2008. I love everything but the fuel mileage (V10, won't buy a Ford 6.0 diesel). Now maybe the GM frame under the vans has been beefed up since 2007, I don't know.
I bought a new 1976 GMC Vandura "Terravan" conversion in June of 1976. 400 small block, TH350 tranny, full-time 4wd. And drove this thing all over the country but primarily the back roads of Nevada and Utah for 32 years. One of the first changes was to install a Rough Country part-time kit in the transfer case, then remove all the California smog stuff and install an Edelbrock intake and Holley carburetor which brought my fuel mileage from 8 mpg to 12 mpg. Yes, it was unit-body construction which was very rigid - no body twist at all when I had it in a twist and one front wheel and one back wheel was off the ground. But that "frame" under it was not very strong - after about 10 years of rough dirt roads I had to have reinforcing plates welded to the frame where the transfer case mount bolted up because it was cracking. I drove this thing, generally hauling a dirt bike and camping out in it, for 32 years.
In 2007 it became evident I needed to either completely rebuild this old workhorse or get something newer. I wanted a diesel for the better fuel mileage so I started doing some research and really liked what I read about the GM 3500 vans with the Duramax engine. By the way, people assume that because the GM vans can be equipped with a Duramax, they also come with the Allison tranny behind it. Not so. That tranny is too big to fit underneath the van body so the diesel GM vans get a version of the Hydramatic. I found one of the van convertors in Oregon who was at the time converting a Chevy van so I went to take a look. The guys there told me they would convert a GM van to 4x4 but only under protest. Two reasons. You ended up with a GM van with a lot of Ford parts so getting it serviced was a problem. The other was - even though the GM van was now built body on frame, the frame was not nearly as rigid as the Ford. They had a deep ditch on their lot where they could test a rig's resistant to twist when crossing that ditch at an angle, and also check on how the suspension worked. The Chevy van's frame twisted so badly that the front bumper actually made hard contact with the body of the van. The Ford van, on the other hand, did not exhibit any noticeable twist and that decided it for me. I became a Ford van man. I used to have some photos of the vans crossing that ditch but can't find them right now. This is what I have been driving since 2008. I love everything but the fuel mileage (V10, won't buy a Ford 6.0 diesel). Now maybe the GM frame under the vans has been beefed up since 2007, I don't know.
Clydesdale
Observer
We have been building chev/gmc vans for a couple years now with very good success. Conversions feature gm only parts, and retain all abs and traction control features. Check us out at:
www.sportsman4x4.ca or https://www.facebook.com/Sportsmanlighttruck
www.sportsman4x4.ca or https://www.facebook.com/Sportsmanlighttruck
deserteagle56
Adventurer
So do they have a solid front axle with free-wheeling hubs?
Clydesdale
Observer
These vans feature chev 1 ton ifs front end parts with factory axle disconnect solenoids
Not sure what year or shape of Chevy van that the frame bending was witnessed, but a skilled mechanic that has spent a lot of time under my 2011 3500 (road trek) and many other Ford E series vans that have rolled in and out of there, tells me that the 2011 frame is every bit as stout as the Ford E350's.
It's too bad that while the Ford E series (besides the cutaway) has been discontinued, that folks don't consider the Chevy 3500 Express vans--mostly due to the propagation of some pretty flawed information (at least talking about the newer Chevy 3500 vans).
It's too bad that while the Ford E series (besides the cutaway) has been discontinued, that folks don't consider the Chevy 3500 Express vans--mostly due to the propagation of some pretty flawed information (at least talking about the newer Chevy 3500 vans).