Brief description of Jeep as it currently sits:
2013 Jeep JK 2dr with 3.6L Pentastar and a 6spd manual

Over the years:

• Front Dana 30 swapped for Tera44
• Eaton E-lockers / 4.56 gearing
• 35” BFG KM2s on D-Window steelies
• 2.5” Rubicon Express lift with all adjustable control arms
• Fox 2.0 shocks
• Stainless steel brake lines
• Synergy flip kit and drag link
• Synergy front track bar
• Synergy frame-side track bar bracket
• Rock Hard Sport cage
• Tom Woods 1350 drive shafts
• Shrockworks mid front bumper
• Warn winch
• Teraflex spare tire mount
• Rear bumper delete and EVO shackles
• KC and Rigid aux lights
• JKS front sway bar disconnects
• JCR aluminum flat / narrow fenders
• Hyline front fender liners

Circa 2022 - I started having cam position related CEL codes and ultimately the heads and cams grenaded at 140k mi. I’ve been saving $$$ for the LS ever since.

05/01/24 - Ordered an all aluminum 5.3L LC9 with worked aluminum heads, DoD and VVT delete from a local resto-mod / hotrod shop

5/29/24 - Ordered Bruiser conversion kit and 8HP70 auto trans $22550.00

6/28/24 - Picked up motor - Engine Shop claims 375HP / 415ft/lb TQ $5800.00 (note that the Jeep will be dynoed to confirm - I will share the dyno printout here)

10/21/24 - Bruiser conversion kit delivered

11/4/24 - Jeep / Engine / Transmission and conversion parts kit shipped to Rock Your 4x4 via local Hotshot Trucking Co $1700.00

Total spent so far: $30050.00

Known future expenses:

• $5000 for motor install
• $1750 to replace AC system that failed recently
• $??? Starter
• $??? Flex plate
• $400 Cat back exhaust (not included in kit)

Future plans after LS conversion:

• Teraflex rear free float kit
• Teraflex front free float with big brake kit
• Anti-Rock rear sway bar (note: this item removed from build due to towing requirements)
• TrailReady 8 lug beadlocks
• Rebuild CAs
• Rebuild shocks
• 37 BFG KM3s
• Synergy rear track-bar
• Synergy Tie-rod
• Synthetic winch rope and fairlead (replace steel cable)

 

Looking forward to watching this come together. This is a long-term goal of mine!

 

At this point you really have no choice, it’s go time. YOLO!

 

I’ll enjoy watching this happen. As discussed today IRL, I’m here to help - or commiserate - as it goes. Just beware the “while we’re in there” scope creep that I fell into! You will love it when it’s done. I love your scope and plan.

 

Thank you for taking my call to discuss. You are right about scope creep - if only we had unlimited budgets! 😎

 

Finally on the way to Rock Your 4x4!

 

Officially in Rock Your 4x4’s capable hands!

I met with Owner, Jason today and per his advice, we decided to add a PSC steering box and Synergy tie Rod. The plan is to run just the box without the ram-assist, since I do not plan to run more than 37s.

if I ever decide to go bigger (likely won’t) then the ram assembly can be added then. This will give me a much stronger pitman shaft that is not likely to shear.

So, the PSC steering added about $3000 to the build. Jason explained that doing the box now, while the engine is out will cost nothing in labor - the install is covered in the motor install labor price already. I will post steering invoice later.

 

Change of Plans...

I was initially going to do the axle work, 37s, and beadlocks as part of a Phase 2 initiative next spring, but I think that will cut it too close to our planned Ouray trip in July. I need time to do some local shake-down runs before attempting a multi-state wheeling trip. Consequently we decided to add the following scope now, as opposed to later:

• Teraflex Rear Free Float Kit $1,425
• Teraflex Front Float and Big Brake Kit $1,900
• x5 BFG 37X12.50R17LT MUD-TERRAIN T/A KM3 $2,210
• x5 Dirty Life 9312 Mesa Beadlock Wheels (matte black) $2,475

Total spent so far: $38800

 

Change of Plans...

I was initially going to do the axle work, 37s, and beadlocks as part of a Phase 2 initiative next spring, but I think that will cut it too close to our planned Ouray trip in July. I need time to do some local shake-down runs before attempting a multi-state wheeling trip. Consequently we decided to add the following scope now, as opposed to later:

• Teraflex Rear Free Float Kit $1,425
• Teraflex Front Float and Big Brake Kit $1,900
• x5 BFG 37X12.50R17LT MUD-TERRAIN T/A KM3 $2,210
• x5 Dirty Life 9312 Mesa Beadlock Wheels (matte black) $2,475

Total spent so far: $41800

That didn’t take long! It will be great when done!

 

Just pulling the band aid off all at once is easier in the long run; but, it's easy for me to spend your money!

 

Yes, but it sure is a painful yank! Yikes! 😬

 

A note about the wheel selection…

I wanted to get a set of Trail Ready beadlocks in 17x9 with a 8x6.5 bolt pattern. The TR bead lock priced out $660 per wheel, with a total cost of $3300

By comparison, Dirty Life 9312 Mesa beadlock came in at $495 per wheel, with a total cost of $2475. They look very similar to the TR beadlock.

By going the Dirty Life route, I saved $825

Here’s the wheel I chose (incorrect bolt pattern shown, but I couldn’t find an image in 8x6.5)

And here’s the TR bead lock that I did not choose:

 

Why am I doing this to a twelve year old Jeep?

1. Economics
2. Sentimental attachment

If I were to replace my current JK with a modern, similarly equipped JL, it would likely cost $80k And it would probably have the same underpowered Pentastar 3.6 engine.

I’ve already invested a substantial sum of money, upgrading the jeep over the years. So investing $50k to rebuild this JK into something special is actually cheaper than buying new - and I get the Jeep I’ve always wanted, as opposed to starting over.

Lastly, and most important, are the memories I gained, in the 141k miles of driving that Jeep. It has endured the most glorious abuse. Being new to wheeling I got to experience places like Hot Spring, Hidden Falls, Stoney Lonesome, Wind Rock, Big Bend, Ouray (Alpine Loop) and more.

I had the honor of introducing this to my Dad after he retired and we wheeled Tennessee and Colorado in this jeep.

My Dad also helped me build the camper trailer shown earlier in this thread.

I lost my Dad to brain cancer September 2022. So the Jeep and the off-road camper will be cared for until I’m no longer around, and they will be passed down. I hope my son gains memories and experiences his own adventures in it!

Rest in peace Dad - you did good!

 

Wow! Your story touched my heart. Tell me something though, I feel similar with my 2007 Jeep wrangler Sahara has 194,000 miles on it, so i feel like i have to prepare myself to part with it, but here yours have less miles, but i hear you are gonna pass it on. Yes, you probably guessed it, i am female.

Can you hold on to it, pass it on, cause all you guys know how to work on it yourself, and keep it running? Mine runs fine, but trying to save up for a more recent year, cause I know nothing about mechanics. Let me know what you think, please

 

Project looks fun!

Officially in Rock Your 4x4’s capable hands!
View attachment 4621718

I met with Owner, Jason today and per his advice, we decided to add a PSC steering box and Synergy tie Rod. The plan is to run just the box without the ram-assist, since I do not plan to run more than 37s.

if I ever decide to go bigger (likely won’t) then the ram assembly can be added then. This will give me a much stronger pitman shaft that is not likely to shear.

So, the PSC steering added about $3000 to the build. Jason explained that doing the box now, while the engine is out will cost nothing in labor - the install is covered in the motor install labor price already. That brings the total spent so far to about $33,000.

Change of Plans...

I was initially going to do the axle work, 37s, and beadlocks as part of a Phase 2 initiative next spring, but I think that will cut it too close to our planned Ouray trip in July. I need time to do some local shake-down runs before attempting a multi-state wheeling trip. Consequently we decided to add the following scope now, as opposed to later:

• Teraflex Rear Free Float Kit $1,425
• Teraflex Front Float and Big Brake Kit $1,900
• x5 BFG 37X12.50R17LT MUD-TERRAIN T/A KM3 $2,210
• x5 Dirty Life 9312 Mesa Beadlock Wheels (matte black) $2,475

Total spent so far: $41800

Technically PSC doesn't recommend just the box over 35" tires because of frame and bolt issues. Any chance you could get the ported box and run it without the assist so you can test it? If you are staying with just the box, I would recommend upgrading the bolts and adding half of a Sector shaft brace and track bar brace to strength the frame. I run a Synergy brace from my stock box and continued with it when I ran the full PSC kit. The PSC box has 2 blind holes on the box so be careful to select proper length bolts if you upgrade.

I have the Teraflex 8 lug kit and like it. It was fairly easy to do but I had a minor issue with a finicky front ABS sensor that needed replacement even though I couldn't find any obvious issue. I also has an issue with a front hub ABS v-ring seal that had some dry rot and split and fell off. The v-seal is hard to find and sorta expensive for what it is. I still haven't replaced it but I don't have mud or water issues here in Colorado. I have checked the hub for water intrusion and there has been no issue. For extra insurance I also upgraded to Stage 8 spindle locking nuts and they can be expensive if you don't hunt around.

What backspacing di you buy with the wheels? If you do upgrade axles down the road are you going to go with 70"-72" wide Dana 60s? I know my Dana 44s with full float kits should be strong enough with my gutless 3.8 2-door but I imagine the V8 is going to stress your axles more. I went with 4.75" backspacing on my beadlocks and use custom Bora 1.5" wheel spacers so that if I ever decide to go with wider axles I will be able to use my existing wheels.

Here is my PSC box, Synergy brace, and upgraded bolts.

This was a good thread where many of us discussed the PSC box and ram if you want more info.

https://www.wranglerforum.com/threads/psc-big-bore-and-cylinder-assist-installation.2426064/#replies

 

I recall seeing elsewhere that the Teraflex float kits require the narrow wheel sensor to fit properly, and that the larger diameter sensors will not work.

Regarding the brace, I’ll ask the shop about the Sector shaft brace (I previously and incorrectly referred to as the “Pitman” shaft…). Bear with me, I’m still a layman.

I already have the synergy frame-side bracket installed and intend to keep it in place. I do not recall if the brace came with different bolts - if it did then I would have used them. Otherwise I would’ve used the OEM bolts with the OEM box. Your suggestion to use stronger bolts is a great idea, and I’ll be sure to do just that.

The wheels have a 4.53 backspace and a -12mm offset. I’m praying my D44 setup will handle the V8. I did speak with Teraflex customer support. One of their technicians has been running an identical setup on his LS swapped 2dr for five years without issue 🤞

Since this is a 2dr build, I really, really don’t want to spend the coin on a D60 setup and hope I will not need to - time will tell.

My philosophy has always been to run OEM until something breaks, and then upgrade. With my use case (pulling a camper in the mountains and mild to moderate rock crawling) I think the build choices I’ve made fit that pretty well. I cannot imagine that I would ever go bigger than 37’s, especially considering that my Jeep spends 90% of the time on tarmac. it is not trailered, it is driven.

Thanks for the thread link on steering; I’ll review it.

 

Excellent post! Got a 2011 JKU w/ 155k miles and the 3.8. Keep the info coming..
Very inspiring..✌

 

LS swap kit for a newer Wrangler sounds very interesting for making a better Jeep as long as you already have a newer jeep its a smart move for a less problematic engine and done right should last a long time

 

I agree. In fact, I’ve heard the conversion kits are more refined for the newer 3.6 than the older 3.8.

I know there are some folks here on this forum that have done an LS for their 3.8 with success, but I’ve also heard the swapping out a 3.8 has its own unique issues.

 

All I can say great tribute to dad. I have attachments to my Jeeps. I bought used Jeeps cause that's all I can afford. My'97 Th was starting to show it's age,it had 173,000 miles when I got it. It now has 240,000. My wife and I are getting up in age (76, 70)and the Th was getting harder to get in. we like to much to part with it. I bought a 2014 jku this year, it looks brand new. I guessing it had been in an accident and rebuilt. So we're keeping the'97. New fenders and it will look better. I'm taking the roof off and making a summer ride out of it. On the '14 I couldn't see any frame damage and it drove straight and true. It had 111,000 on it and with cash paid $15 k. With replacing the the side rails to with a greater drop. And we were happy. Till it hit 112,000 miles then the engine seized. Well back to the'97 till we made up our minds what to do with it. We decided replacing the engine. At $9k it was cheaper than replacing the hole Jeep,now it runs and looks new. I can't wait till summer to get back in the '97. It's a standard shift so nobody can drive a shift so it's all mine. And yes they both are street vehicles, I gave up mild off reading years ago. Your right it's more than a car it's a Jeep with great memories.

 

I’m sorry to hear about your 14’ JK dieing at 112K mi.

Not to bash on Chrysler / Jeep, but I’ve seen dozens of posts on this forum, and others, of folks having major head / cam / timing issues at relatively low mileage (like mid-60k mi).

Like you, I got a $9k quote to fix mine from a Jeep Dealer - that was not a whole motor, only replacing the top end - That was a big Nope.

Every older car that I have owned went well over 200k - so my takeaway from that is, “they don’t build ‘em like they used to.”

I mean that today, it’s all about weight and fuel economy. So literally things that SHOULD be made of steel, are instead built with plastic.

Consequently, I think all modern cars are DESIGNED to be disposable- the manufacturer expects you to buy new every 100k mi.

At the prices the dealers ask for Jeeps, the disposable car marketing strategy is a no-go for me.

If done correctly and maintained, I expect to get 200k + miles out the new LS.

 

ChrisL,
It's been a long, long time since I posted on this forum. And through basic email notifications, I get an email notice every so often regarding what's been happening on the Wrangler forum, as I do with other forums. And one of the topic/threads highlighted was this one, about your JK/LS conversion. So, I just got to this thread.

I have been dreaming of this conversion applied to our '15 JKUR for years and years. This is our 9th Jeep. (3) CJ's, (2) YJ's, (3) TJ's (2 rubicons ) and our present one, a 2015 JK Unlimited Rubicon. So, needless to say, been around Jeeps for a few decades. WE did Moab for 14 years in row during the Easter Jeep Safari. And we've seen just about every alteration of a Jeep known to man. If I'd have been smarter in life in terms of throwing money at sooooooo many Jeeps over my lifetime, and saved it, I'd have WAAAAAAAY more than enough to do the 500HP version/conversion. But, no one's ever accused me of being smart.

But an LS conversion, in my opinion, is the top-of-the-line thing to do, no doubt about it. I've been a DIY type ever since Christ was a pup. Welder/fabricator/wood worker/ and more for decades, along with a career as a fireman. As much as I'd love to dive into a project like you're in with this conversion, I just don't know at 72, if I've got enough stamina to handle a project like this, start to finish and turn the key.

But, I'm sure gonna follow each step and progress report. You are definitely living the dreams I've had for years. Thank you for the high quality writeup and documentation. Very, very much appreciated. Good luck. By the way, we're waaaaay out here in Lake Havasu AZ.
Scott

 

ChrisL,
It's been a long, long time since I posted on this forum. And through basic email notifications, I get an email notice every so often regarding what's been happening on the Wrangler forum, as I do with other forums. And one of the topic/threads highlighted was this one, about your JK/LS conversion. So, I just got to this thread.

I have been dreaming of this conversion applied to our '15 JKUR for years and years. This is our 9th Jeep. (3) CJ's, (2) YJ's, (3) TJ's (2 rubicons ) and our present one, a 2015 JK Unlimited Rubicon. So, needless to say, been around Jeeps for a few decades. WE did Moab for 14 years in row during the Easter Jeep Safari. And we've seen just about every alteration of a Jeep known to man. If I'd have been smarter in life in terms of throwing money at sooooooo many Jeeps over my lifetime, and saved it, I'd have WAAAAAAAY more than enough to do the 500HP version/conversion. But, no one's ever accused me of being smart.

But an LS conversion, in my opinion, is the top-of-the-line thing to do, no doubt about it. I've been a DIY type ever since Christ was a pup. Welder/fabricator/wood worker/ and more for decades, along with a career as a fireman. As much as I'd love to dive into a project like you're in with this conversion, I just don't know at 72, if I've got enough stamina to handle a project like this, start to finish and turn the key.

But, I'm sure gonna follow each step and progress report. You are definitely living the dreams I've had for years. Thank you for the high quality writeup and documentation. Very, very much appreciated. Good luck. By the way, we're waaaaay out here in Lake Havasu AZ.
Scott

Glad you joined the thread. Expect an update on progress mid-next week - I was told that they are in the process of installing the accessory drive stuff on the new motor (power steering, water pump, intake, alternator, AC etc). Hopefully I’ll get some photos of that stage so I can share them here.

By the way, I’ve never been as far west as AZ, but it is on my bucket-list to visit and wheel there!

 

I did not know there was so much information on it until I searched

Google Search

 

For the sake of brevity, and sharing the info with others, this is the kit I purchased, less the 6.6 engine:

2012 – 2018 | 500HP 6.6L LX3 V8 engine and 8-speed conversion for late Jeep Wrangler JK and JKU

Powerful, integrated, turn-key 500 hp LX3 V8 engine and upgraded strength 8-speed transmission package for the late model 2012-18 Jeep Wrangler JK and JKU. Transform your life by adding Bruiser’s bolt-in combination of legendary power and reliability from the GM Performance small-block V8 engine...

bruiserconversions.com

Hence the reason I paid $22550, not $34950 - meaning the engine portion of the complete kit costs $12400. The 5.3 all aluminum engine I bought for $5800 is estimated to put out 375 HP, which is 125 HP less than the 6.6 option. For me, I do not think I’ll miss that 125 HP and I saved $6600 having my own Gen IV LS built.

Given this project is for a 2dr, I think the 5.3 is a better choice. I will get better gas mileage and be able to run 87 octane.

I think a mildly tuned 5.3 will be more streetable for my application.

 

For the sake of brevity, and sharing the info with others, this is the kit I purchased, less the 6.6 engine:

2012 – 2018 | 500HP 6.6L LX3 V8 engine and 8-speed conversion for late Jeep Wrangler JK and JKU

Powerful, integrated, turn-key 500 hp LX3 V8 engine and upgraded strength 8-speed transmission package for the late model 2012-18 Jeep Wrangler JK and JKU. Transform your life by adding Bruiser’s bolt-in combination of legendary power and reliability from the GM Performance small-block V8 engine...

bruiserconversions.com

Hence the reason I paid $22550, not $34950 - meaning the engine portion of the complete kit costs $12400. The 5.3 all aluminum engine I bought for $5800 is estimated to put out 375 HP, which is 125 HP less than the 6.6 option. For me, I do not think I’ll miss that 125 HP and I saved $6600 having my own LS4 built.

Given this project is for a 2dr, I think the 5.3 is a better choice. I will get better gas mileage and be able to run 87 octane.

I think a mildly tuned 5.3 will be more streetable for my application.

Chiming in for the benefit of others - You and I discussed this live of course, but for the benefit of others reading this … the 5.3 is 100% the right solution for a Jeep pretty much regardless of application IMO. I did the 6.6 because “more power” and while it’s a laughably powerful beast on my pretty built up JKU, it’s literally too much power (I can’t believe I’m saying this!) and it’s thirstier than I ever imagined it could be (8 city/11-13 hwy on 37’s and 4.56 gearing). I am enjoying it, it ticks every teenager box I have (loud, raucous, surprisingly fast, did I mention loud?) but in the spirit of learning lessons, it really is too much power for the chassis/suspension. You’ll love it, I love mine, but I strongly recommend the 5.3 to everyone!

 

Here is a company that sells kits click and scroll down

MOTECH PREMIUM CONVERSIONS

THERE IS NO EQUAL Direct injected GM LT1 engine, combined with GM's 8 speed transmission represents the pinnacle of V8 engine conversion technology.

lswrangler.com

 

I did reach out to MoTech before settling on Bruiser and Rock Your 4x4

MoTech is (or has) moved away from LS swaps in favor of the new LT swap, due to LS availability. I got lucky and found one for a reasonable price. I had a local resto-mod shop build it to spec. I got to choose the cam profile. I decided on a mild 6.2 cam profile (I’ll check the build sheet and post the numbers here).

I learned that cam profile has a significant impact on where in the RPM range torque ramps up. Higher TQ at lower RPM usually means a mildly tuned engine. Making TQ early in the rpm range is generally a good thing for a 4x4. So no crazy tuning beyond a mild cam IMHO.

Regarding the LT, I’m not really interested in an engine that has Displacement on Demand (DoD) and Variable Valve Timing (VVT) like most crate engines do. I had my LS built without DoD and VVT. That’s why I prefer the LS over the LT crate engine.

While MoTech has a vast amount of experience, their quote came in about $10k more, and there is the problem of proximity. I live much closer to Knoxville than Las Vegas; making Bruiser and Rock Your 4x4 an easy choice.

 

Updates???

 

I plan to touch base with Rock Your 4x4 regarding progress on Monday.

stay tuned….

 

11/13/24 - Update

Not much to report at this early stage.

- The wheels and tires that were ordered are at the shop.

- Water pump, AC compressor, and motor mounts installed

 

Invoice update:

$3750.96 for:

• X2 GM Steam Port Bolts - $13.86
• GM LS Steam Port Block off Kit - $20.98
• 10046031 Flexplate Roll Pin - $4.20
• PSC Big Bore Steering Gear and Pump Package - $2712.39
  • gearbox
  • pump kit
  • reservoir kit
  • cooler
  • hoses
• 8002-15 Synergy Tie Rod - $420.00
• 8807-03 Synergy Stabilizer Clamp - $72.00
• 4421 GoatBuilt T/C Pump and Alternator Bracket - $189.95
• Note: Flex plate was included in kit -N/C

Known future expenses:

• $5000 Motor install
• $500 Misc AC components
• $??? Starter
• $400 Cat back exhaust

Total spent so far: $42,550.96 - Keep in mind that this total includes the motor / trans AND the full float kits, wheels and tires, and PSC steering.

 

You will love it, and as noted, great call on the full float kit. You are making good decisions.

 

11/27/25 Update:

I spoke with Jason at Rock Your 4x4 yesterday.

• Flexplate and bell housing adapter installed
• PS pump and alternator bracket installed
• PSC pump installed

Awaiting parts from Bruiser:
- Alternator (N/C)
- ECM (N/C)
- Bell housing alignment dowel pins (N/C)

Shop to begin removing body from frame around 12/10/24 - There’s another Jeep build in progress, so I’m waiting on that lift to become available.

Ordered Teraflex 8x6.5 spare tire bracket for my Teraflex Alpha tire carrier to match the new bolt pattern - $194.00

Total spent so far: $42,745.96

I got an estimate from the shop regarding additional labor cost for bead lock wheel and tire build, and front and rear free float install.

- $250 to build beadlocks
- $720 to install free float kits

Labor invoice to be paid when the Jeep is done.

 

Update 12/04/24

Rock Your 4x4 was able to sell my old wheels and tires for a $600 credit! Hopefully I’ll be able to sell the 6spd manual transmission too.

Total spent so far reduced to: $42145.96