Author Topic: Cummins or Duramax or Detroit thoughts  (Read 16842 times)

Offline Engineer

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Cummins or Duramax or Detroit thoughts
« on: December 01, 2014, 07:05:47 PM »
Everybody is doing the Cummins swap thing. If I were going to build a rig with a diesel I'd go Duramax. If for no other reason than to be different.

The Cummins will probably be cheaper, but I'm a GM purist and would love a square body with a Duramax to tow with.

The Cummins is an excellent engine, you just don't find them in anything GM.

Anyhow, OP, good luck with your build.
2002 Chevy 2500HD 4x4 8.1/ZF6sp RC/LB
2001 Chevy 2500HD 4x4 6.0/4L85E EC/SB
1997 Chevy Blazer 4x4
1994 Chevy K-2500 4x4 C6P 5.7/4L80E
1979 Chevy K-30 4x4 4sp 4.10
1977 Chevy K-30 4x4 4sp 4.10 454

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Offline flips87c30

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Re: Cummins or Duramax or Detroit thoughts
« Reply #1 on: December 01, 2014, 08:20:23 PM »
Thanks. I haven't heard great things about the duramax. Plus I wouldn't know where to start. There is a lot of information on the Cummins swap. I do get where your coming from though. Unfortunately I am not the guy for the job. I'm going to have my hands full just swapping in a Cummins
« Last Edit: December 01, 2014, 08:30:34 PM by flips87c30 »
87 v30 duelly dump truck 454, th400, np205, dana 60/14 bolt, warn hubs, gmt800 mirrors and LEDs all around the bed.

Offline LTZ C20

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Re: Cummins or Duramax or Detroit thoughts
« Reply #2 on: December 01, 2014, 10:10:56 PM »
As engineer said, I would also use a Duramax,  I work with them every day and they are very reliable and can also be upgraded alot. Not to mention,  the Cummins being so big is a tight squeeze, the Duramax engine itself is about the size of a 454, so there's enough room and probably won't be as hard to squeeze in the engine bay.
LTZ Cheyenne C20

Offline Captkaos

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Re: Cummins or Duramax or Detroit thoughts
« Reply #3 on: December 01, 2014, 10:25:28 PM »
I think he is pretty committed to the Cummins, moving this off out of his project post if we want to discuss Duramax setups.


Now I too would do one.  Here is one in a 4x4:
http://www.lonniesperformance.com/82chevyduramax.htm

2wd:
http://www.dieselpowermag.com/features/chevy/1303dp_1976_chevy_c10_the_ultimate_swap/
« Last Edit: December 01, 2014, 10:31:59 PM by Captkaos »

Offline pocale

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Re: Cummins or Duramax or Detroit thoughts
« Reply #4 on: December 02, 2014, 10:50:31 AM »
Two characters: V and 8  ;D

Offline flips87c30

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Re: Cummins or Duramax or Detroit thoughts
« Reply #5 on: December 02, 2014, 11:13:06 AM »
I think we could go back and forth all day about whether Cummins or dmax is better. There are tons of threads all over the internet doing just that. But I can find a Cummins for a couple thousand bucks around here all day long. No such luck for a duramax. Maybe they are out there though I don't know
87 v30 duelly dump truck 454, th400, np205, dana 60/14 bolt, warn hubs, gmt800 mirrors and LEDs all around the bed.

Offline zieg85

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Re: Cummins or Duramax or Detroit thoughts
« Reply #6 on: December 02, 2014, 11:18:47 AM »
Someday I hope to talk a childhood friend of 45 years out of his 67 C20 that has a 3-53 Detroit Diesel in it.  The truck is rotting where it sits but it sure was a neat yard truck some 30 years ago when I used to run around in it.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline OneLowOneTon

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Re: Cummins or Duramax or Detroit thoughts
« Reply #7 on: December 02, 2014, 02:03:07 PM »
Would love to put a 4-53 Detroit in mine but without a body lift the motor is entirely to big. Love the sound of a good Detroit. Am contemplating the same decision right now as I am debating a diesel swap in my truck.

Offline 1HI4x4

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Re: Cummins or Duramax or Detroit thoughts
« Reply #8 on: December 02, 2014, 02:14:20 PM »
Hard to beat the simplicity and raw torque of a Mechanical Pump Cummins........ I have one in my V30, I have owned several big block square bodies and there is no comparison in the power. 6 in a row is the way to go.........

I understand the purist wanting a Dmax in these trucks, they are a ton more complicated to install and not nearly as easy to upgrade. I can change all 6 injectors in my Cummins before you can pull one in a Dmax.

I would love to have a GM Allison behind my Cummins though.
1988 V30 Crew Cab, Cummins power, 47RH-NP205, 8" lift, 13.50x35x20 Fuel Mudders on 20x14 XD Diesels -76 offset. Soon to be repainted, seats from a 2010 Lariat to be installed.

Offline OneLowOneTon

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Re: Cummins or Duramax or Detroit thoughts
« Reply #9 on: December 02, 2014, 03:34:57 PM »
Have considered just putting in a 6.5 turbo. Truck is not used for pulling just for show and driving. How you put the price difference between maintenance and up keep between running a diesel and gas? Or a Cummins and dmax?

Offline roundhouse

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Cummins or Duramax or Detroit thoughts
« Reply #10 on: December 02, 2014, 05:53:06 PM »
GM purist ?

I thought the duramax was designed and built by Isuzu ?

And the 6.2/6.5 was designed and built by Detroit ?
« Last Edit: December 02, 2014, 05:57:08 PM by roundhouse »

Offline 1HI4x4

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Re: Cummins or Duramax or Detroit thoughts
« Reply #11 on: December 02, 2014, 05:55:32 PM »
Like.......
1988 V30 Crew Cab, Cummins power, 47RH-NP205, 8" lift, 13.50x35x20 Fuel Mudders on 20x14 XD Diesels -76 offset. Soon to be repainted, seats from a 2010 Lariat to be installed.

Offline Captkaos

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Re: Cummins or Duramax or Detroit thoughts
« Reply #12 on: December 02, 2014, 08:18:06 PM »
OneLowOneTon, I know a few people personally that daily a lowered 88-99 dually with a 6.5L turbo.  As far as maintenance I think it would be a toss up I guess.
The 6.5L will probably yeild more fuel mileage that a gasser in the 1 ton.  And it will bolt right in place.  I put a 6.2L in mine for the same reason.
Keep in mind that if you use a 88-98 turbo 6.5 you will have to modify the AC ducting.

I like the Duramax due to the outside the norm but they are pricey.  I can tell you if a Cummins came up I would be very tempted though as long as it was mechanical.

Offline OneLowOneTon

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Re: Cummins or Duramax or Detroit thoughts
« Reply #13 on: December 02, 2014, 09:40:12 PM »
Roundhouse the 6.2 and 6.5 are Detroit's and were designed by the GM division Detroit Diesels.
I'm still looking into the 6.5 turbo swap, I will removing my heater and ac box and smoothing the firewall some so I will have the extra space for the turbo and downpipe. But ialso have my eye on a mechanical 5.9 right now. Just curious as to the mod and cost difference to go Cummins

Offline LTZ C20

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Re: Cummins or Duramax or Detroit thoughts
« Reply #14 on: December 03, 2014, 01:56:30 AM »
6.5 all day long, or Duramax.  I love Dmax's, great engine. But I also love the clatter and noise from a 6.5 at idle that just screams "I'm A DIESEL!"
LTZ Cheyenne C20