Cummins Turbo Diesel swapped 2012 JKU build

Holy lift! Why 6" and a 1" body lift!?

I went with the 6" Teraflex lift originally because I wanted to easily be able to clear 40's someday and I wanted the longarm suspension. Bruiser Conversions installed the 1" body lift with the conversion for some components to be given enough clearance.
 

highoctane

Caught the Bug
Seems like this engine should be a better candidate for a diesel swap than the old 4BT. Have you had any problems with having the engine revving to close to redline on the highway? That seemed like a potential problem with 5.38 gears and 40s with the 4BT swap that Bruiser has done, highway rpms at 75 - 80mph being too close to the 4bt redline.
 
Seems like this engine should be a better candidate for a diesel swap than the old 4BT. Have you had any problems with having the engine revving to close to redline on the highway? That seemed like a potential problem with 5.38 gears and 40s with the 4BT swap that Bruiser has done, highway rpms at 75 - 80mph being too close to the 4bt redline.


I am running 3:73 gears on 37's and I can run at 70 mph at 2200 rpm. The Jeep redlines at 3200. The new Dynatracs have 3:54 gears so I should be able to run a little lower RPM.
 

hinrichs

Caught the Bug
Very cool build. Was wondering about the body lift as well but never thought about it being needed to clear some of the engine and parts, which totally makes sense. Did you get a video of the dyno run?
 

cozdude

Guy with a Red 2-Door
I went with the 6" Teraflex lift originally because I wanted to easily be able to clear 40's someday and I wanted the longarm suspension. Bruiser Conversions installed the 1" body lift with the conversion for some components to be given enough clearance.

you can run 40's on a lower lift if you wanted and keep the long arm. as for the body lift that makes sense for engine clearance
 

highoctane

Caught the Bug
I am running 3:73 gears on 37's and I can run at 70 mph at 2200 rpm. The Jeep redlines at 3200. The new Dynatracs have 3:54 gears so I should be able to run a little lower RPM.

That's not too bad. I guess you could just run a lower geared xfer case like an Atlas to get the low crawl ratio back. Does it still crawl at a decently slow speed with a 4:1 low range?
 
Very cool build. Was wondering about the body lift as well but never thought about it being needed to clear some of the engine and parts, which totally makes sense. Did you get a video of the dyno run?

Yeah I did. It's on my Instagram @GreenJeepMac.
 
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That's not too bad. I guess you could just run a lower geared xfer case like an Atlas to get the low crawl ratio back. Does it still crawl at a decently slow speed with a 4:1 low range?

It actually does, even with my 3:73 gears. The Dynatracs are coming with 3:54 gears, and I still think it will crawl nicely.
 
God man I really wish I had the money to do the diesel swap now but I don't believe I will be able to for quite a while, definitely jelly of your set up.

My justification for the swap was that my Jeep had 50,000 miles on it and was out of warranty, and rather than spending a lot of money on a new Jeep, why don't I just spend a little less money and improve my Jeep while also making it "new" again in a way, because the new engine has zero miles. Plus, you will never get out of your Jeep what you have in it with the mods that you do to it, so why buy a new Jeep and have to spend another pretty penny to modify it in the way you want to when you could just improve and refresh the one you have already put your time and money in to? Thats why I did it.
 

LSX-Jeep

New member
Man I love your build!!! Right now I'm doing a Ls supercharged conversion but with that being said I would have rather gone with my 5.9 24v Cummins that I have in the garage. Hey maybe on my next build:).
 
Man I love your build!!! Right now I'm doing a Ls supercharged conversion but with that being said I would have rather gone with my 5.9 24v Cummins that I have in the garage. Hey maybe on my next build:).
The I6 Cummins is a really awesome engine but not really ideal to swap into a Jeep unless you're building a monster with at 42" or larger tires, like Rattletrap. Otherwise, it is just way to heavy to put in the front of a Jeep. The 4 cylinder is perfect for a Wrangler. It's an awesome balance of lightweight, fuel economy, and power.
 

LSX-Jeep

New member
I hear ya:). I'll be using dyna 60 and 80s as well and running in 40s on the streets and 42s on the rocks.
 
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