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Ideal Drivetrain for Crew Cab and why

CUCV2

CUCV2

5/4 ton fun
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Just trying to generate some ideas for an 87 crew cab I bought. The body/frame is completely rust free and a good foundation for a project. I have some CUCV axles to put under it. So, the drivetrain would have to accomodate the 4.56 gears. It originally had a 454/TH400/205 but they are gone. Leaning towards an 8.1L at the moment. It supposed to bolt right in.
 
I would do a duramax Allison too. It's less intrusive than the cummins i.e. not as loud.

The 8.1 would be good too though but dream drivetrain is a duramax Allison combo.
 
If it were a manual trans I wouldn't even consider the nv4500. Only a zf 6 speed. Ratios are better 4500 still suffers the same 3 to 4 ratio on the 465. At least if your in the mountains. And towing really heavy loads. I just like the ratios on the 6 speeds better
 
I think running an Allison will put a kink in your plans if your front end has a passenger side drop. From what I read it's hard to get a passenger side drop tcase on them without $$$

I'm planning the same project and I'm going 8.1L with a nv4500 or 4L80e. Both have good tcase options and are readily available for a reasonable price.
 
I'd go LSX454/4l80e/atlas. LS motors kick ass, good strong trans with overdrive and twin sticks negate the turning radius.
 
Thanks for the replies. While I do think an Duramax/Allison combo would be a great mix of new technology in a classic Chevy, the reality of cost comes into play. I do have access to a Cummins 2nd gen 12 valve truck for a great price, a Vortec 454 (also for a great price), and an 8.1L.

The main two determining factors for choosing which option to put in are time and cost. Having three kids has pretty much negated any projects that require extensive time commitments. So, finding a drivetrain with minimal extra mods and the most benefit would be ideal.

The Cummins 12 valve truck would be my first choice if I had more time and $. It is currently mated to a blown auto tranny. I would want either the NV4500 or NV5600 to put behind it. This choice would mean a new xmember/motor mounts, clutch, hydro pedals, plumbing an intercooler, and finding a tranny in good shape. So, basically it would require time and money.

The Vortec 454 actually seems like the best option at the moment. It is also mated to a blown transmission but I have a good 4L80e and a passenger drop NP205 in storage. They would bolt right in and the truck is already set up for both. Not sure what the electrical harness requirements are and if it is or isn`t a drive by wire set up though.

The 8.1L is also a viable option. The main obstacle to this has been finding a good one for a decent price. The ones that I have found have been mated to an allison. That means figuring out how to get a passenger drop transfer case mated to it. Two solutions I know of are getting an Atlas transfer case built or 2wd Allison with a divorced transfer case. Neither option sounds appealing. I could mate the 8.1L to a NV4500 but again, that is more time and money that I don't have.

The purpose of this truck will be to use it as a tow rig for a camper and the wheeler. No off-road excursions for this truck as I plan on keeping it a long bed and having a clean example of Chevy crew cab.

The path of least resistance seems to be the Vortec 454. My questions for this transplant are;

1- Will it have enough power to move a crew cab, family of five, and whatever I want to tow behind it?

2- What would be involved for wiring it up? Can I use the existing 454 Vortec harness for the tranny controller somehow?

3- What input (long or short) will I need to connect the transfer case to the NP205? It currently has the 32 spline long. Will it bolt right up? The 4L80E originally had a NP241 driver's drop TC and that is the adapter that it has.

I will try to get some pics up so you all can see what we are working with.
 
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I absolutely love my Cummins / NV4500 swapped crew cab. It tows whatever I want it to and gets good mileage while doing it.

Whatever drive train you decide to go with, make sure it's what you want, rather than what's convenient. There's nothing worse than spending time and money on a truck only to wish you had done it differently.
 
sweetk30 said:
why not newer 6.0 or 6.2 ls and 6l80 or 6l90 and the 205 behind it with kit from advanced adaptors to put 205 fig 8 behind the 6 speed auto gm . http://www.advanceadapters.com/categories/adapter-kits/191/0/0/0/0/0/107/0/
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Idk man. LS's dont really shine when you're loaded down with people, gear, camping stuff, and towing. Underneath all that advancement and great power numbers they are still constrained to the world of the small block.





The TBI454 really isnt exactly a gem and IMO its not worth what you'll get out of it.

Im an 8.1 lover. I towed a lot of serious **** with one for quite a while so I have a soft spot for them. They pull just like a diesel and would like the 4.56s more so than a diesel. I cant believe theres no way at all to get an older tcase behind an allison.

O and the allison is the only auto Ive ever liked in a truck btw...
 
If you end up with a manual behind a cummins look for a nv5600. I loved mine in my 02. Essentially it splits the gap between 3-4 so it's way more useful when towing. Other than that. All these options sound good.
 
Stomis said:
The TBI454 really isnt exactly a gem and IMO its not worth what you'll get out of it.
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He wants to swap a Vortec 454 in not a TBI 454....
while the Vortec 454 isn't an 8.1 it is still much better then a TBI 454...
 
I have read that both 454 TBI and Vortec heads like to crack easily (eventhough the Vortecs do flow well). Basicly, all GM assembly line heads are crap, but the GEN-V 454 Vortec block is the best of all the GEN and MARK blocks. I have read that the ultimate combination is a Vortec GEN-V block (roller cam, better oiling system), and a set of aftermarket (such as World Products) large ovel port MARK-IV heads (which do bolt directly on, and flow better than Vortecs). Aftermarket head castings are twice as thick as GM assembly line heads, and last forever, if only driven on the street and abussed only a little bit.
 
1-ton said:
I have read that both 454 TBI and Vortec heads like to crack easily
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This is true for the Vortec 454 heads? I have only read and experienced this firsthand with the 350's

I have been wanting to upgrade my dd to a set of Vortecs but haven't got around to since it is my dd. Should I not mess with a set of junkyard heads? (due to messing with cracks)
 
Is there some reason you couldn't use a 4L80E behind an 8.1? I believe Vans were configured this way, they even used the 4L80E behind the Duramax in Vans.
 
Yes some 8.1s have 4l80s behind them and all duramax vans came with them too.
 
My Suburban has a 4L85E. That would be a nice set up. Just have not seen one. If I wait a few more years, I could use the drive train out of the Suburban. The salted roads in winter should have it just about ripe by then :rolleyes:.

This is thread is about finding the right drive train. And about finding a balance between that and time and money. I would rather drive something with a decent drive train than watch it sit in the garage because of a lack of time to work on it. Been down that road. Maybe when the kids get older that will change but right now it feels like spare time was a dream I had a long time ago.
 
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