How Feasible is a Duramax Swap?

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Cataldo
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How Feasible is a Duramax Swap?

Post by Cataldo »

I Know that the Duramax is bigger and heavier than the 6.5 Detroit even, let alone price.

I would Imagine the electrical swap would be on par with an LSX engine. To my understanding it has the same bellhousing as a SBC/BBC/Detroit Diesel but different motor mounts. Is it all the difficulty of a 6bt swap with double the cost?

Thanks
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



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prairiejeeper
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Re: How Feasible is a Duramax Swap?

Post by prairiejeeper »

giving up on the 6.5 so soon?

I can't imagine the 6.6 will be as cheap as a 5.3 conversion, which is what I consider the second cheapest option. The cost for a 6.6 would likely be similar to cummins swaps, and cummins wins that comparison most days.
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Stuka
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Re: How Feasible is a Duramax Swap?

Post by Stuka »

Very costly, you will want to do some frame re-enforcements, and I would venture to say its a harder swap than an LS. There is a huge market for swapping in LS engines, so lots of kits and software to do it. Thats not the case for Duramax.

A 6BT is a bit more work to fit the engine due to its length. But is otherwise an easy engine to swap, and lots of support for it too.
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Re: How Feasible is a Duramax Swap?

Post by srobertsfsj »

It's doable, IIRC the Arnold Schwarzenegger Wagoneer had a duramax/allison in it. It was done by a custom duramax shop tho.
Last edited by srobertsfsj on Fri Nov 06, 2015 10:44 am, edited 1 time in total.
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Cataldo
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Re: How Feasible is a Duramax Swap?

Post by Cataldo »

Thanks, I was figuring it would be more difficult than it was worth.

Prairiejeeper, nope just putting out all feelers.
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



Looking for 1 good factory Kidney Bean Mag in Southern California for use as a matching spare
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Pablo
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Re: How Feasible is a Duramax Swap?

Post by Pablo »

There are many Duramax variants. Most swapers use the LB7. Not sure how hard it is to swap. It weights around a 1000 pounds wet. A 4bt is around 850 wet and a 6bt is around 1250. I think the 6.5 GM was around 700 or 650. Something with an Allison would certainly be better reliability wise than the GM autos behind the old 6.5. A Duramax Allison transfer case combo is long though and may give you driveline headaches, especially if you plan a lift. From memory, the Duramax engine is not as tall or long as a Cummins 6bt, but wider.
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Re: How Feasible is a Duramax Swap?

Post by husker77 »

The one Arnold had looked to me to be a wagoneer body swapped onto a gm frame, it had the ifs front suspension.
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Re: How Feasible is a Duramax Swap?

Post by Stuka »

husker77 wrote:The one Arnold had looked to me to be a wagoneer body swapped onto a gm frame, it had the ifs front suspension.
Correct, it was a waggy on a shortened GM chassis.


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Re: How Feasible is a Duramax Swap?

Post by Mudbull »

I don't know how the price of the donor engine would be, but it looks like a stand alone harness is close to the cost of an LS harness. Being a v8 configuration, I bet there would be minimal firewall and tunnel work, but frame reinforcing would be the same as a 6bt swap. My swap doesn't have any driveline angle issues, I can't see how a duramax driveline could be longer.

I'd love to see it done, but to me I don't think you can beat a cummins swap for simplicity and cost if you want a diesel, or an LS swap for gas (I'm bias though).
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Re: How Feasible is a Duramax Swap?

Post by WaggyGuy »

If you want a Duramax, I don't know if I'd go with the LB7. They are supposed to have slightly better fuel economy than the later versions, but they have their drawbacks. The LB7 is known to eat injectors quite often and they are a pain to replace. They are hidden under two separate valve covers per side. Injectors run $150-200 each and take 5+ hours to swap each bank if I remember correctly. I've read about people getting as much as 100,000+ miles from injectors or as little as 15,000. Just something to consider.

As for size, I've got an LB7 with Allison tranny so I can probably get you some measurements if you'd like to have them. It's 4x4 too.
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