Squarebody on a Duramax frame

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Zach Painter

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Anyone here done a body swap to a Duramax frame? Looking to do one with my 83 and curios as to what needs to be done for body mounts.
 

Charlie

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:welcome:
 

roundhouse

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I’ve never done it but I would predict the Body mounts will be the easiest problem to solve

All the wiring and computer and harness mods are going to be the real headache
 

shiftpro

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It won't fit without completely redesigning the firewall... and floor.
Your frame is stronger anyway...
 

Matt69olds

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I bet the new fully boxed frames are far stronger than the old C channel frame, not to mention the ride quality would be much better. The biggest hassle I could see if trying to adapt the ABS and all the modern conveniences. I would imagine a body lift would solve most of the floorboard and firewall issues. I’m pretty sure Painless Wiring makes a wire harness with a PCM that will run the engine, I know I have seen them for the Cummins.

Unless you could figure out how to keep all the advantages of the newer frame under the classic body, I’d swap the engine into the older frame. Less headaches. Maybe someone has already done what your attempting. I think it would be badass if done, all the modern advantages with the classic body looks
 

roundhouse

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You try typing
“Duramax squarebody”
in google or DuckDuckGo ?

Why anyone would want a zillion expensive sensors and a expensive computers on a old pickup , I don’t know , but here ya go .

I’d use a 12 valve Cummins and a five speed.
cheaper ,easier and more reliable with no computer

Using a dmax isn’t keeping it GM since GM was not capable of designing or manufacturing a new diesel and had to pay Isuzu in Japan to do it for them

I’d also start with a K-30 frame .
Noticeably stronger than the K10 or 20 frame

But if you put those retarded giant rims on it ......

https://www.dieselarmy.com/features/car-features/the-perfect-swap-lml-duramax-swapped-1986-gmc/


https://www.google.com/amp/blog.cal...fitted-with-a-built-640hp-duramax?hs_amp=true

https://www.steelsoldiers.com/showthread.php?178733-Duramax-Diesel-Engine-Conversion-Kit
 
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SquareRoot

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When I went to Barrett Jackson in Scottsdale last year I saw the most awesome, beautiful truck I ever imagined. A crew cab, shortbed K20 (87 I believe) with a 2014 duramax/Allison trans. All the interior was swapped over including dash and leather seats. It looked factory original. Black on black. The literature said it had a one off frame built by one of the well known chassis shops. I don't know what the cost in dollars and time was but the point is it can be done. It's just how bad you want it.
 

Craig 85

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Here's a You Tube video of a guy making the swap.

xc_hide_links_from_guests_guests_error_hide_media
 

DoubleDingo

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I'd put a 60's Series truck body on a Square Frame before I went the route you're considering.
 

Zach Painter

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You try typing
“Duramax squarebody”
in google or DuckDuckGo ?

Why anyone would want a zillion expensive sensors and a expensive computers on a old pickup , I don’t know , but here ya go .

I’d use a 12 valve Cummins and a five speed.
cheaper ,easier and more reliable with no computer

Using a dmax isn’t keeping it GM since GM was not capable of designing or manufacturing a new diesel and had to pay Isuzu in Japan to do it for them

I’d also start with a K-30 frame .
Noticeably stronger than the K10 or 20 frame

But if you put those retarded giant rims on it ......

https://www.dieselarmy.com/features/car-features/the-perfect-swap-lml-duramax-swapped-1986-gmc/


https://www.google.com/amp/blog.calibratedpower.com/blog/85-square-body-fitted-with-a-built-640hp-duramax?hs_amp=true

https://www.steelsoldiers.com/showthread.php?178733-Duramax-Diesel-Engine-Conversion-Kit



I don’t like dodge, not doing the swap “to keep it gm”. If that’s your reasoning then powerstroke isn’t Ford and Cummins isn’t dodge since neither of those 2 made their own. Ford finally did in 2011 but still.
 

Zach Painter

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I bet the new fully boxed frames are far stronger than the old C channel frame, not to mention the ride quality would be much better. The biggest hassle I could see if trying to adapt the ABS and all the modern conveniences. I would imagine a body lift would solve most of the floorboard and firewall issues. I’m pretty sure Painless Wiring makes a wire harness with a PCM that will run the engine, I know I have seen them for the Cummins.

Unless you could figure out how to keep all the advantages of the newer frame under the classic body, I’d swap the engine into the older frame. Less headaches. Maybe someone has already done what your attempting. I think it would be badass if done, all the modern advantages with the classic body looks



Duramax tuner has an 85 that’s sitting on a 2003 chassis. Trying to see how they went about it but no answer from them yet.
 

roundhouse

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I don’t like dodge, not doing the swap “to keep it gm”. If that’s your reasoning then powerstroke isn’t Ford and Cummins isn’t dodge since neither of those 2 made their own. Ford finally did in 2011 but still.


The 6BT was designed by Cummins to be used in excavators
And it’s in a lot of boats too
The marine pump and injectors is a nice upgrade
At least dodge was the only one to not act like it was their own engine
And the NV 4500 was also used in Chevys

I think everyone knows what happened when ford designed their own engine
The 6.0 disaster

For the poster worried about the ABS and stuff

All that is going to stay just like it is with the late model chassis
It’s just getting a old body dropped on
Changing or modifying the floor and firewall isn’t that hard if you have a good quality mig welder and practice a little

Hot rodders have been modifying floors since the 40s
To Channel a body lower onto a frame

I’ve modified several to fit a transmission or T-case that wasn’t factory
 

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