2006 Chevy 3500 Duramax-Cummins Swap

deerefanatic

Always learnin...
Yep. You read this right. The Duramax is coming out!

After a lot of messing around, the LBZ left me walking. To be honest, I've not been crazy impressed with the LBZ since I bought it, and the fact that it has now failed me twice is the last straw.. Truck has 230k miles on it, and last fall the headgaskets blew.. Changed em, put in ARP's. Had the heads checked by the local machine shop. Put in 3" downpipe and deleted the EGR equipment while I was in there. Fast forward to 2 weeks ago, pulling my goosneck through the mountains in West Virginia. Truck kept overheating on hills, I was down to 40 mph to keep the engine under 240. Fan clutch was kicking in, water pump replaced last summer. Thermostats a few years ago. Next morning I made it 5 miles from the hotel when water temp skyrocketed and headgaskets (I'm assuming) let go and left me sitting on the highway in a puddle of water on the ground. For the record, my tow tune was a stock tune with EGR delete, my daily driver tune was a fuel mileage tune. Don't think I ever went wot with the fuel mileage tune ever..

I still have the 12v Cummins that was in my old 88 Chevy Dually conversion that I parted out. Looks like I'm going to be using Screamin' Seeman's motor mounts, destroked adapter plate, and work with them on a controller (since I already have the factory TCM and wire harness, I don't need the entire destroked setup). This motor was twinned, and made 502hp @ 1900 rpm; 1250 ft-lbs @ 1850 rpm (Rear wheel measurements on a superflow). It was a dream to tow with.

Friend of mine that does transmissions is going to go through the Allison for me and build it. Goerend converter and Alto G3 clutches.

Any other build advice from anyone? Anyone looked at figuring out how to defuel a 12v for shifts to help the Allison stay together?
 
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Got the LBZ pulled out of the truck this weekend. Got the tractor partially stripped down. I'll be pulling the motor out of it next to put in the truck..
 
How much do you want for the lbz?

Should probably do more than a clutch upgrade to that trans if you ever plan to turn it up more.
 
Ditch the Allison for good

There's no reason to, it'll hold everything his setup can throw at it when set up correctly.

Unless these conversion guys haven't got the software worked out to be compatible, then a built 48re would out weigh the headache.
 
There's no reason to, it'll hold everything his setup can throw at it when set up correctly.

Unless these conversion guys haven't got the software worked out to be compatible, then a built 48re would out weigh the headache.



its not about holding the power:doh::doh:
 
Air conditioning is tricky but doable-still better than the GMT 900 trucks, I can look up my diagrams and give you pointers. Not sure on the trans stuff as I am a manual guy, I have built a couple swaps and I am a couple hours east of you in Clinton, MI. Feel free to PM me
 
Cummins is sitting in the truck. I have the "freightliner" style hi mount ac bracket, and ordered a Sanden 4666 A/C compressor to bolt to it. Have a 28si J180 mount 200 amp alternator that I bought brand new for that department. Have to figure out yet where to mount the tensioner with this setup. Also hoping to figure out the belt routing this weekend.

Hot pipe and turbo mount from Crazy Carls just got delivered today. Going to test fit with my dummy turbochargers (as the ones I'm going to use are out getting some goodies done to them) hopefully this weekend.

Thinned the LBZ wiring harness. I'm keeping the basic dash sensors plus fuel temp, intake temp and boost. Might as well use the ECM and my V2 for datalogging on this Cummins. :)

I'll try to get pics soon.
 
Not bad. Sounds like you're doing it right so that's a positive. Hope you get the allison to play nice with the 12Valve.
 
There is a guy local to me that put a 6 speed Allison behind a 12v. Was in a 06 superduty though, has good results. Believe he told me got all stuff from Howard's Allison.
 
I’ve put many Allison’s behind cummins
I own three. I think it’s a awesome combo
60,000 on my 05 since the 6 speed swap running compound chargers
I have another in my pulling truck- p-pumped 6.7 for the last 9 years
 
I’ve put many Allison’s behind cummins
I own three. I think it’s a awesome combo
60,000 on my 05 since the 6 speed swap running compound chargers
I have another in my pulling truck- p-pumped 6.7 for the last 9 years

That last part is impressive. Any build info? What are you controlling it with?
 
That last part is impressive. Any build info? What are you controlling it with?

Hate to hijack a thread
But yes a Allison from a Lbz, complete billet internals, stall is as high as Phil can get it. Northeast’s latest 13mm with 6x .024’s. I was running Destroked old setup with only 4th gear commanded, then coming out and locking converter. Had a lot of people tell me that it wasn’t possible. Had some issues late this season with the trans controller. We found out that I was exceeding the rpm limits and the thing was defaulting and shifting. If I want a knowledgeable guy talk to Jason at transmission tuner. We figured out my issue and gonna go at it strong in first parts of season
Here’s a link to a pull this year

DOUBLE DOWN DIESEL. 397 - YouTube
 
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