Well I've been away from the forum for a while and I really haven't done anything new to the Jeep for most of 2018 other that drive the hell out of it and we wheeled quite a bit. My wife and I have attended about 4 Jeep rallies over the summer, one of which we hosted in Ouray, CO in August and the Jeep has performed flawlessly other than the same old complaint I've had since day one, low on power. Well I have been contemplating and planning a power upgrade for over 4 years now but with us moving two years ago and then having to put in a yard and build a new shop the power upgrade project was postponed. However, this past spring I again began planning out the build and decided to start collecting parts and pieces for the upgrade.
I will be removing the anemic 3.8 liter V6 from my 2011 Jeep Wrangler Unlimited and will be installing a ... 6.2 liter all aluminum Chevrolet LS V8 engine along with the 6L80 automatic transmission. This combination has been one of my favorites for a while now and I have been working through the EPA bullshit in order to get it to pass the strict emissions laws here in Utah. Hands down the number one reason for this engine/transmission swap is drivability, everything else is second to that. The new Jeeps don't impress me, I have this chassis/suspension built the way I want it and would like to keep this Jeep on the road (and trails) for at least another 15 years and a couple hundred thousand miles.
Those of you who have followed along on my threads or posts have probably figured out that I am a GM guy moreso than any other brand, with a HEAVY mixture of Jeep in there.
I've had them all but prefer the bowtie, what can I say. Nearly from day one with my Jeep JKUR after lifting it and the initial build I have dreamed of having some LS V8 power but I also wanted to keep the Jeep dependable, reliable and have ALL of the creature comforts working and not settle for just another V8 swap like so many have done and have all kinds of idiosyncrasies or quirks about it. I have merely settled for the anemic power levels on the road because it wheels so great and has taken on anything and everything I have thrown at it off-road. It is the on-road performance that really has bothered me. There are times when it can't get out of its own way, even with the 5.38 gears on the small 35" tires. Sad that 35" tires are now considered small~ish. I have also informed my wife that now that I have the power to go a bit bigger on tires I will be stepping to 37" tires after the swap as my 35" BFG KO2's are nearing the end of their usable tread. The tire has been a fantastic tire and I have loved them both on and off road. My Jeep now has 92,500 miles on the odometer and these tires have been on for 48k miles now and flat towed another ~18k miles over the past 4 years so I am very happy with the life I have gotten and especially with their performance both on and off road. I could probably get another 6-10 out of them if I wanted but by the time I get the swap done and get some miles on it and then purchase tires I will probably have another 1-2k miles on these. My wife was frustrated with me wanting to go up in tire size, probably because she is a bit vertically challenged and has a hard time getting in now but it should only lift it about an inch or so which I think she can handle. She was worried that with the larger tires I would want to do more extreme trails but I insured her that I am not putting larger tires on to do more aggressive trails, merely to get over the obstacles on the trails we are already running just a bit easier and less dragging on my skids and control arms. I'm not looking to do more technical trails than we already run.
I have been so focused on the house, shop and yard over the past two years that the Jeep has been put on the back burner as far as upgrades so I have just been driving it and wheeling it and enjoying it but this past summer I decided to get serious about upping the power and started doing much more homework diving into EPA regulations as well as wiring and trying to anticipate integration issues.
I have been wrenching for over 30 years and have done many engine swaps over those 3-decades but this one is a bit more interesting due to the CAN network system and keeping everything EPA compliant. This will also end up being the most expensive engine swap I have ever done which is largely due to keeping everything EPA compliant. The days of merely dropping in a small block Chevrolet engine and TH400 transmission, hooking up a fuel line and distributor are pretty much gone.
This past summer I started collecting parts & pieces for the swap and knew exactly what years and what particular engine or engines would be most viable. I determined I wanted a 2010-2014 LS engine in order to meet the USEPA guidelines for engine swap. I contemplated the 5.3, the 6.0 as well as the 6.2 liter engines. The 5.3 would obviously be a great deal better than the 3.8 V6 that is currently in my Jeep but I doubted I would be happy for very long being only 1.5 liters larger and my Jeep is on the heavy side at 6k pounds. I then thought the 6.0 which would work as it was designed for heavy hauling in the GM trucks if you didn't get the Duramax. This engine will put out easily 350~ish HP and around 385 lb/ft of torque and haul my Jeep around beautifully. Plus with the iron block be very durable and withstand the extreme temperatures better here in Utah. All the while however, I kept thinking the 6.2 liter would be the cat's meow. Again, my wonderful and loving wife told me not to settle so the 6.2 LS engine it is. The LS3 is a great engine which was available in the Camaro's and Corvette's but I wanted the low end torque of the 6.2 LS truck/SUV engine with its taller intake (longer runners) and VVT (Variable Valve Timing). The LS3 would also be a bit better fit seeing as the intake is lower but the truck engine will fit just fine, plus the LS3 is harder to find as a lift out and brings a premium in new form. The entire GM package (6.2 LS engine/6L80 transmission) is only about 45 pounds heavier than the iron block 3.8 V6 and 42RLE transmission that is currently in my Jeep so it shouldn't affect suspension or handling at all, hell I think my winch was heavier than that. The 6.2 LS truck/SUV engine will put out just over 400 hp and nearly 420 lb/ft of torque in stock trim with OEM GM tune so that is what we are going with, although I will more than likely tweak the tune and probably shift points down the road. After a little bit of searching for a low mileage lift out engine and transmission I found a 6L80 transmission with 38k miles on it from a 2012 GMC Denali but the engine was already spoken for, damnit!!! About two week later I got a tip and after a few phone calls I landed me a brand new L94 crate engine from GM, which is no longer available other than a long block.
Introducing my new 6.2 L94 that will reside in my 2011 Jeep JKUR.
Here is the 6L80 transmission from a 2012 GMC Denali and the NP241J from a 2008 Jeep Sahara with the 2.72:1 low ratio.
For those wishing to upgrade the power of their JK, there is quite a bit of information out there and several viable options but after my research this is the direction I chose to go as I am really not impressed with the 3.8 or even the newer Pentastar 3.6 for that matter. I also don't really like the Hemi option as we've wheeled with several over the years and that was never really one of my choices.
I will try to keep this updated as the project progresses.
