Humvee bodyswap to civi truck frames

[RPMRPM]

Not sure weather this is the right thread or weather it needs to be in normal hmmwv thread but I’m thinking about dropping a humvee body on a 2nd gen dodge 12v truck frame with the 12V Cummins 47RE NP241HD with the Dana 80 rear and 60 front for a overland truck to keep all the driveline I’m familiar with and I can gets parts for at any parts store basically if I need something on a long trip I was wondering if anyone had any experience dropping a humvee body on 1st or 2nd gen or similar civi truck/SUV frames and has any advice

 

[MarkM]

Bpy that will be a huge endeavor.

 

[Mogman]

I'm not sure why you would give up all the comfort with the same off road capability as the doner civy truck.
One big issue you are going to have is the engine will be past the front bumper with no room to install the hood and absolutely nowhere to put the radiator.
The entire engine is well behind the front axle on the HMMWV and moving the drive train on the civy chassis will be a chore and the rear drive shaft angle will be extreme, the portal axles and half shafts put the differentials in a good position for such a short wheelbase.
That will be an interesting conversion, start a build thread when and if you start doing it, and yes this is the correct forum.

 

[RPMRPM]

I'm not sure why you would give up all the comfort with the same off road capability as the doner civy truck.
One big issue you are going to have is the engine will be past the front bumper with no room to install the hood and absolutely nowhere to put the radiator.
The entire engine is well behind the front axle on the HMMWV and moving the drive train on the civy chassis will be a chore and the rear drive shaft angle will be extreme, the portal axles and half shafts put the differentials in a good position for such a short wheelbase.
That will be an interesting conversion, start a build thread when and if you start doing it, and yes this is the correct forum.

Yeah I already have a complete humvee I think I talked to you about it with the twin turbo 12V in it and a 47RE which is a ton of fun but I’ve already broken a half shaft not sure what kinda upgrades they offer for them so that’s why I’m thinking about having 2 swapping the crazy high horse twin turbo engine to the civi frame and putting a like 400-500 horse single turbo 12V Cummins engine in the real humvee in hopes it holds up to that better

 

[tobyS]

Are you keeping it 4x4 ?

 

[Mogman]

Not anything I know of unless you have the 10K Basic or A1 drive train, nobody needs crazy HP unless they are doing some type of exhibition driving.
I have not been able to break the 7/10K drive parts with 425HP even though I am running part time 4WD.
But again I don't do any rock climbing, none around here.
How did you break the half shaft?

 

[Mogman]

You could buy all new half shafts, break them down and have them cryo treated

 

[RPMRPM]

Are you keeping it 4x4 ?

Yeah either a NP241HD or a predator T-case so it can be full time 4WD still like a humvee still

 

[RPMRPM]

Not anything I know of unless you have the 10K Basic or A1 drive train, nobody needs crazy HP unless they are doing some type of exhibition driving.
I have not been able to break the 7/10K drive parts with 425HP even though I am running part time 4WD.
But again I don't do any rock climbing, none around here.
How did you break the half shaft?

Well the one that’s in it now is a just under 800WHP twin turbo Cummins not a matter of need it’s just fun and people reactions are comical when they get passed by it like they’re standing still lmao. Same reason I love my 98 dodge diesel

 

[RPMRPM]

You could buy all new half shafts, break them down and have them cryo treated

Mine had the 7k’s I think although I’ve done a few boosted launches and that probably doesn’t help the trans holds up fine as I knew it would from my truck i Might try 10k’s and if that doesn’t work go to 12K’s if a body swap would be that much of a pain before I give up

 

[RPMRPM]

You could buy all new half shafts, break them down and have them cryo treated

Would I need to worry about the reduction hubs braking after I get the half shafts up to a 10-12k assuming they don’t brake or would you not worry about those?

 

[RPMRPM]

Not anything I know of unless you have the 10K Basic or A1 drive train, nobody needs crazy HP unless they are doing some type of exhibition driving.
I have not been able to break the 7/10K drive parts with 425HP even though I am running part time 4WD.
But again I don't do any rock climbing, none around here.
How did you break the half shaft?

I would rather stick with the humvee diffs half shafts and hubs since I love the ground clearance for off-roading too but I wanna make sure I don’t have to worry about it breaking on long trips either

 

[86humv]

Before the first Hmmwv's were sold at auction in 99....people put bodys on chevy Suburban chassis....and one guy put
one on a Dodge d300 1978 chassis.
I have a body in central / west Texas.

 

[Mogman]

Well the one that’s in it now is a just under 800WHP twin turbo Cummins not a matter of need it’s just fun and people reactions are comical when they get passed by it like they’re standing still lmao. Same reason I love my 98 dodge diesel

A few months ago I blew the doors off of a jeep that had the back window full of hot rod parts stickers including a Procharger decal, I looked in my rear view mirror and he had his hands up in the air, like what the heck just happened,,, classic!!!
Even at only 425HP the gear ratio gives it a pretty awesome launch.
I would think with even just 10K half shafts if you acted like an adult when on a long trip I doubt you would have any issues.
My engine has a big Fleece turbo, the larger injectors and high performance pump, it had obviously been rebuilt before I bought the donor truck so it may have some high performance guts also, it had DSP-5, and a 5" exhaust, I figure it should be good to 650HP or so, I do wonder what effect the high performance parts have on the 425HP tune but I need a bigger intercooler to push it any farther, as is I am pretty happy

EDIT, it was unfortunate but the DSP tunes can only be downloaded to the ECM they cannot be "read" so I have no idea what tunes were in it when I got it, and the ECM had an input damaged when the truck rolled shorting out a bunch of stuff so I had to replace the ECM.
I have considered installing DSP-5 as I have the switch needed, then I could "bump it up" when I wanted someone to "hold my beer"

I pulled the sub pan a couple months ago and there was not a spec of "mud" in the pan and nothing on the pump screen so it obviously does not have the 300K that was showing on the donor odometer, it also has twice the warm oil pressure my other LMM has that does have 300K on it.
I was hoping to be able to see the rods but there was not much view of them with just the sub pan off, I was hoping to see Carrillo on them

 

[Mogman]

What transfer case do you have behind the 47RE?
The one I am running is a MP1265 I THINK, it is the original from the 2008 C2500HD, I LOVE that electronic shift on the fly!!!!

 

[RPMRPM]

A few months ago I blew the doors off of a jeep that had the back window full of hot rod parts stickers including a Procharger decal, I looked in my rear view mirror and he had his hands up in the air, like what the heck just happened,,, classic!!!
Even at only 425HP the gear ratio gives it a pretty awesome launch.
I would think with even just 10K half shafts if you acted like an adult when on a long trip I doubt you would have any issues.
My engine has a big Fleece turbo, the larger injectors and high performance pump, it had obviously been rebuilt before I bought the donor truck so it may have some high performance guts also, it had DSP-5, and a 5" exhaust, I figure it should be good to 650HP or so, I do wonder what effect the high performance parts have on the 425HP tune but I need a bigger intercooler to push it any farther, as is I am pretty happy

EDIT, it was unfortunate but the DSP tunes can only be downloaded to the ECM they cannot be "read" so I have no idea what tunes were in it when I got it, and the ECM had an input damaged when the truck rolled shorting out a bunch of stuff so I had top replace the ECM.
I have considered installing DSP-5 as I have the switch needed, then I could "bump it up" when I wanted someone to "hold my beer"

I pulled the sub pan a couple months ago and there was not a spec of "mud" in the pan and nothing on the pump screen so it obviously does not have the 300K that was showing on the donor odometer, it also has twice the warm oil pressure my other LMM has that does have 300K on it.
I was hoping to be able to see the rods but there was not much view of them with just the sub pan off, I was hoping to see Carrillo on them

Oh yeah absolutely people don’t realize how amazing diesel torque is for speed along with gearing. I daily a 500 Horse 24V Cummins and it’s a ton of fun but the humvee launching under boost is running high 11’s in the quarter mile so it blows even RT chargers away and depending on the driver I’ve outrun a few hellcat too lmao reactions are comical as you can imagine. It’s all mechanically injected so I have to drive it very sensibly on the street since if I don’t it will smoke wayyyy to much

 

[RPMRPM]

What transfer case do you have behind the 47RE?
The one I am running is a MP1265 I THINK, it is the original from the 2008 C2500HD, I LOVE that electronic shift on the fly!!!!

What transfer case do you have behind the 47RE?
The one I am running is a MP1265 I THINK, it is the original from the 2008 C2500HD, I LOVE that electronic shift on the fly!!!!

The 5 pos one from predator Inc 4WD Hi, 4WD Low, 2WD (for killer burnouts), AWD, neutral. I think it was like 3k or something the AWD is nice for bad weather with that much power & torque, but it was more than I wanted to spend on a case but honestly I don’t regret it since I drive it a lot and love it so much the guy I talked to said they run it behind their 1,200 horse Cummins humvee and have had no problems

 

[Mogman]

In 2WD if you bust it loose at at over 20-30MPH does yours try to swap ends?, mine does, good fun!!

 

[RPMRPM]

In 2WD if you bust it loose at at over 20-30MPH does yours try to swap ends?, mine does, good fun!!

Yeah it does lmao. what is really fun is when I’m pulling on someone on the highway and I give it a little too much throttle so the big turbo hits harder than usual at 70 and the rears bust loose and spin for a few seconds before hooking back up lmao. It impressive and super cool but if your not expecting it it’s sketchy

 

[RPMRPM]

A few months ago I blew the doors off of a jeep that had the back window full of hot rod parts stickers including a Procharger decal, I looked in my rear view mirror and he had his hands up in the air, like what the heck just happened,,, classic!!!
Even at only 425HP the gear ratio gives it a pretty awesome launch.
I would think with even just 10K half shafts if you acted like an adult when on a long trip I doubt you would have any issues.
My engine has a big Fleece turbo, the larger injectors and high performance pump, it had obviously been rebuilt before I bought the donor truck so it may have some high performance guts also, it had DSP-5, and a 5" exhaust, I figure it should be good to 650HP or so, I do wonder what effect the high performance parts have on the 425HP tune but I need a bigger intercooler to push it any farther, as is I am pretty happy

EDIT, it was unfortunate but the DSP tunes can only be downloaded to the ECM they cannot be "read" so I have no idea what tunes were in it when I got it, and the ECM had an input damaged when the truck rolled shorting out a bunch of stuff so I had to replace the ECM.
I have considered installing DSP-5 as I have the switch needed, then I could "bump it up" when I wanted someone to "hold my beer"

I pulled the sub pan a couple months ago and there was not a spec of "mud" in the pan and nothing on the pump screen so it obviously does not have the 300K that was showing on the donor odometer, it also has twice the warm oil pressure my other LMM has that does have 300K on it.
I was hoping to be able to see the rods but there was not much view of them with just the sub pan off, I was hoping to see Carrillo on them

Also other than going to 10k’s do you think I’ll be fine in the way of the diffs and reduction hubs Or should I look into options for those?