Duramax vs Cummins HMMWV Conversions

[4x4nutz]

Two things.

This is a dead thread from 2018. Holy ICE Batman. Detroit Diesel internal combustion engine swaps are hard.

This thread needs to be moved to mods and conversions.

So what is hard about it and how many have you done?

 

[Mogman]

Done, also 4X4nuts is making duplicate posts

 

[goobie]

I would love to see a 6b crammed into a hmmwv I just couldn't imagine 2 extra cylinders crammed in there

This is when I was finishing up the swap. Got @40k miles on it since then, No regrets

 

[Mogman]

This is when I was finishing up the swap. Got @40k miles on it since then, No regrets

Do you have any more photos of the conversion? if so please post!!
Also what trans and transfer case did you use? Was that a mechanical Cummins or common rail?

 

[goobie]

Do you have any more photos of the conversion? if so please post!!
Also what trans and transfer case did you use? Was that a mechanical Cummins or common rail?

I made an album on Facebook BUT I have since been evicted from Facebook. I will start with uploading pictures

What are the pros and cons of each engine? I'm specifically talking about the predator conversions that they offer.

Lets hear some arguments for each side!

What are the pros and cons of each engine? I'm specifically talking about the predator conversions that they offer.

Lets hear some arguments for each side!

duramax is the easier of the two swaps. I went the cummins route because i have seen a lot more cummins engines with 800k+ miles than a duramax. i have been making a living as a mechanic for over 35 years, I have owned my mechanic shop for 21 years. I always prefer to work on a cummins than a duramax just from a simplicity standpoint.

 

[Mogman]

I made an album on Facebook BUT I have since been evicted from Facebook. I will start with uploading pictures


duramax is the easier of the two swaps. I went the cummins route because i have seen a lot more cummins engines with 800k+ miles than a duramax. i have been making a living as a mechanic for over 35 years, I have owned my mechanic shop for 21 years. I always prefer to work on a cummins than a duramax just from a simplicity standpoint.

What makes it more difficult than a Dmax conversion, is that an Allison trans?

 

[goobie]

What makes it more difficult than a Dmax conversion, is that an Allison trans?

2006 the civilian H1 Alpha came with a duramax , So the mounts and brackets are available. All the Cummins mounts are custom made. That is one reason it is more difficult.
Yes 6 speed allison

 

[Mogman]

2006 the civilian H1 Alpha came with a duramax , So the mounts and brackets are available. All the Cummins mounts are custom made. That is one reason it is more difficult.
Yes 6 speed allison

I was not aware anything was available, I believe all those parts have been sold, there also would be no cross member because the Alpha used the 4L80 trans.
There is however some adapter plates to adapt the Dmax to the original motor mounts but some other mods need to be made as the engine sits higher on those adapters, they come from some guys that are sticking Dmax motors in old chevy Impalas
What transfer case is that? that is an interesting looking adapter.
Also how are you controlling the Allison, that is a mechanical 6BT yes?

 

[goobie]

I was not aware anything was available, I believe all those parts have been sold, there also would be no cross member because the Alpha used the 4L80 trans.
There is however some adapter plates to adapt the Dmax to the original motor mounts but some other mods need to be made as the engine sits higher on those adapters, they come from some guys that are sticking Dmax motors in old chevy Impalas
What transfer case is that? that is an interesting looking adapter.
Also how are you controlling the Allison, that is a mechanical 6BT yes?

The 2006 H1 alpha had a 5 speed allison. The transfer case is an modified humvee 242 , it has a clocking ring to get the angle right for front driveshaft. The alison TCM is in one of the pictures, it is mounted in the battery box under the seat. 6BT with mechanical P pump.

 

[Mogman]

The 2006 H1 alpha had a 5 speed allison. The transfer case is an modified humvee 242 , it has a clocking ring to get the angle right for front driveshaft. The alison TCM is in one of the pictures, it is mounted in the battery box under the seat. 6BT with mechanical P pump.

So the TCM does not require any information from a ECM? was it originally driven by a mechanical engine?
I was led to believe the GM TCM needed the ECM to work, I have communication between the ECM/TCM and the TCCM, I love the shift on the fly transfer case and am dang glad I did not install the mechanical transfer case I had bought because I thought it would be easier and no doubt it would have

What gear ratio diffs do you have?

VERY nice build

 

[Mogman]

PM sent

 

[goobie]

So the TCM does not require any information from a ECM? was it originally driven by a mechanical engine?
I was led to believe the GM TCM needed the ECM to work, I have communication between the ECM/TCM and the TCCM, I love the shift on the fly transfer case and am dang glad I did not install the mechanical transfer case I had bought because I thought it would be easier and no doubt it would have

What gear ratio diffs do you have?

VERY nice build

The 242 is a mechanical transfer case. Alison TCM does Not need much to be "stand alone" . I'll include more details and were i got stuff from in the new thread