[LCAC_Man]

So after starting down the path of a Duraburb: http://www.dieselplace.com/forum/63...875154-duraburb-planning-budgeting-phase.html
I realized what I really wanted was an expedition style van.
I'll continue to track budget on this build same as I was on the suburban. I sold the Suburban last week, and returned the radiator. So my starting point with the Duramax/Allison package that I have is $7100 invested. To summarize that is with a new water pump, new front and rear main seals, rebuilt turbo with billet wheel, magnaflow downpipe, full EGR removal, PCV reroute, Nicktane filter adapter, LMM torque converter, Transgo Jr. kit installed and transfer case pump rub kit installed. Engine has 156k on it, trans has 88k on it.
I've made a deal on a 2000 Express 3500 Hightop $8500 and a 2006 Express Duramax 3500 159" cutaway (blown engine) $2000 owner is pulling the box off so I'm picking it up this Thursday.
so I'm at $17600 as it sets now.
There's a couple ways to skin this cat but what I hope to do is move the hightop body over to the cutaway frame after I get everything installed and working on it. (and build rear body mounts and shorten it 4"). This will keep me in a functional vehicle and allow the majority of the problem solving to occur on the cutaway.
Front axle will likely be a coil sprung F350 Dana 60 or maybe a Dodge Dana 60.
I'll also likely transfer the entire dash/wiring from the 06 to the 00 to make it more compatible with my engine/trans package.
I'd like to keep the electric shift transfer case but that's something that I'll get to later. Dash cluster solution will also be a challenge...Any input is welcome...even if you want to tell me I'm off my meds..
Anyways, here's some pic's of what I'll be starting with.

 

[Camaroz1985]

Looks like quite a project, but I will be following along to see how it turns out. I think I remember seeing that the newer body style vans have more room for the cooling stack. Are you going to keep the front end of the cutaway van?

 

[LCAC_Man]

I'd like to keep the original(2000) front clip but the new style is my back up plan, the addition of the intercooler may require it...the old style front clip only ever supported the 6.5TD which wasn't intercooled in the van configuration..

 

[Camaroz1985]

The old style does look better in my opinion though.

 

[LCAC_Man]

The old style does look better in my opinion though.

Agreed...if I can make it work it will stay. My worry is that GM made that nose longer specifically for the extra cooling stack room...we'll see..

 

[The_Ure]

Standalone controller+ old front clip.
You would have the best front end on a duramax van

 

[LCAC_Man]

Standalone controller+ old front clip.
You would have the best front end on a duramax van

That's one way to go, and then just use the data lines to drive some independent/aftermarket monitoring. There's a lot to be said for the earlier system that doesn't live off of CL2 data..
I think my approach is going to be; work on the fabrication first.
Phase 1 will probably be:
1. Pull the cab off the cutaway and get all the measurements for where the new front axle will need to reside and determine what needs to be cut out.
2. Get the blown LBZ/4l80e combo out of there and get the chassis cleaned up.
3. Cut out the engine cross member structure that is in the way.
4. Mock up the new front axle, build mounts for radius arms/track bar and sort out the steering links.
5. Transfer the van specific duramax parts to the new package and install the new LBZ/Ally/NP263 combo
6. Shorten frame from 159" to 155" wb and get drivelines modified and installed.
7. Swap in AAM 11.5 SRW on and remove the DRW Dana80.
8. Install additional body mounts needed for the passenger van.
9. Cab back in place, modified wiring to integrate the two and get it running/driving.
10. After I'm sure I've got a viable fully functional package I'll determine how I want to integrate the 2000 body, I should have a solid understanding of whether or not the older front clip will work(dimensionally).

Going this route will take a little longer but will keep the hightop van functional until I'm sure I know WTF I'm doing.

 

[The_Ure]

Old front will not 'fit' duramax cooling stack, the new front barely does.
There is a reason why the two changes where coincident.
You are custom fitting everything else so... you want the parts to all be 'stock' or you want it to have the grill you want? Nothing stopping you from doing it.
Front axle forward is the only way I can see solid axle fitting right on mine.
Have you considered np27x for your TC or are you set on the 263?

 

[LCAC_Man]

I'm not dead set on the electric shift 263, I have it now so that's what I'll start with, if I have to make a change so be it, the push button shifting is damn nice though..
I got the 06 Cutaway home yesterday and got a pretty good look at it, they definitely jammed 10gal of $hit in a 5gal bucket, a 1.5-2" body lift would buy a tremendous amount of working space.
Also after looking at the 159"wb cutaway frame I think I'm just going to shift the rear axle 4" forward (probably just have new main leaves with offset pin holes made), there is plenty of room in the frame arch and I'm going to be lifting it some anyways so that isn't much of a factor. Then I'll just cut off the excess frame in the back.
I think until I actually get a front axle located under it I won't know exactly how that's going to go. It looks like the coil spring buckets on the frame and the Ford Super 60 coil perches are damn near a match for width, if I could use both and just have custom coils made I'd be happy with that, figuring out radius arm location/attachment is an unknown at this point.

 

[artementy]

The cutaway frame is a C-channel whereas the 135/155" wheelbases van frames are fully boxed...

 

[LCAC_Man]

The cutaway frame is a C-channel whereas the 135/155" wheelbases van frames are fully boxed...

Yes, they increase the height of the frame rail and material thickness on the cutaway to get the strength needed. I don't think there's any real strength concerns with either. The difference in shape is something that I'll need to watch out for, I fly up to Portland on Tuesday to pick up the Hightop, when I get it home I'll map out any of the underbody interferences.
I have a back up plan of using the front portion of the cutaway frame and the rear portion of the high top frame as well; they are all spliced together at the same place underneath the cab when built at the factory. It's a lot of cutting/grinding so I'd prefer not to go this route.
Actually I'd probably just try and source a bare passenger van frame rather than that route to better control the project..

 

[LCAC_Man]

Got home with the Hightop yesterday, logged about 1700miles, got to say the 5.7(L31) is a trooper of an engine...it was over 100dg for 6-7hrs straight on Friday in Central Cal and we had the A/C kicking ,it never even hinted at getting hot. Got a rock solid 15mpgs combined for the hole trip which is saying something because we hit all the falls out on the river gorge in Portland, then Crater Lake, then of course the Grapevine coming home so there was plenty of grade climbing going on..
Everything on this van works and it was a shockingly comfortable ride (not common for an unloaded 3500). I was worried that the wind from big trucks would be an issue with the large hightop profile but I never experienced a bit of that...so far...so good..

 

[LCAC_Man]

After looking it over more closely the biggest obstacle is going to be the much larger engine cover/opening in the duramax cutaway than the Hightop. The body lift I have planned helps, but, it still needs to be larger than it is...there is no easy way to do that, removing and transferring that section of floor over to the hightop and using the larger cover may be the only way to achieve it.
Frame can be shortened (to achieve 155" wb) and the fuel tank will have to be moved forward 8" to get the fill in the right position.
The old style front clip just won't work period, absolutely no room for the lager cooling stack..

 

[artementy]

Correct. In 1996-02 period vans with big block (7.4 and 8.1) and 6.5TD engines used bigger doghouse.
In 2003+ the Duramax doghouse is bigger.
The body panels are cut more on both as well.
Both result in less legroom for the front passenger.
Sawzall and hammer are your friends, but it probably won't look nice.

 

[LCAC_Man]

Just figuring that out now...Thanks for the confirmation.
If the body lift doesn't solve it; I'll probably just count on transferring that section of floor/firewall over to the hightop then just use the larger cover... that's why I bought a donor (I guess..)
Just found this post...trying to get in contact with this guy to see if he got past it..
New guy with van addiction - Duramax Diesels Forum

 

[LCAC_Man]

Have you considered np27x for your TC or are you set on the 263?

Other than work on the tuning/controls for the 263; is there an advantage to the NP271/273?

 

[The_Ure]

Front output flange, strength, offset from center for bigger ujoint clearance.

 

[LCAC_Man]

Front output flange, strength, offset from center for bigger ujoint clearance.

Got it...if the controls for the 263 become too problematic I'll look for a 271 and go manual shift.

 

[LCAC_Man]

So I pulled the engine cover off my cutaway donor to see just how much room I could gain with a small body lift and if I could run a smaller opening/cover setup. Looks like with very little effort I could gain 4" at the rear. Sides are tighter but I think 1.5" is achievable.
On the frame/chassis I decided that modifying the frame from the cutaway was going to be too much work so I found an 06 rolling chassis that I'm going to pick up in about a week.

 

[Camaroz1985]

So what is the cutaway actually donating at this point? Just the front end and wiring/dash?