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Trying to get it mostly right the first time: A 5.9 Magnum and 46RE swapped, Tummy Tucked Daily Driven Jeep TJ

I finally carved out some time to update this thread.

Picking up from where we left off, I decided to take a weekend to get the Jeep back up and running. The short answer is that it's fixed, though I'm not entirely sure what the problem was. I pulled the intake off and re-sealed it (in hindsight that was mostly a waste of time), cleaned and reinstalled the original IAC and cleaned the throttle body and that fixed the issue.

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The test drive for the Jeep was a few trips to work and then a 300 mile round trip to Auburn and though the stalling issue was resolved, it developed a bad misfire that I suspected was due to poor plug wire routing on my end. A few poser pictures from our Auburn trip:

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The misfire got so bad that the Jeep was practically undrivable so this was the next issue to dive into. These engines are known to have an issue with spark knock caused from improper spark plug routing (there's actually a TSB for it), so wire routing was the first thing I confirmed correct. Next I started pulling plug wires one a time and checking for resistance. Sure enough one of my brand new plug wires had gone bad (or I'd broken it) so I threw on an old wire and it's been running like a top since.

Enter January of 2024 and the cold temperatures exceeded my motivation to work outside so I moved to working on things that fit inside my shop. I ran to the farm and picked up the 8.8 I purchased a while back and stripped it, welded the center section to the tubes and primed and tacked the Barnes 4wd truss to prep for the axle swap. I'm shooting to swap the axle out this summer once I've sold a few jet skis to replenish my project fund.

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No real updates on the TJ as it's been serving part time DD. Total miles on the swap to date is 5,779. I've been collecting parts for the next round of work, including 3.5" JKS Dual Rate Springs, a set of JL Fox shocks and am planning out the cooling system changes / upgrades / modifications as well.

I do have an update on a Jeep related bucket list thing that I've wanted to do for going on 20 years.

I first subscribed to Peterson's 4 Whell and Off Road in August of 2003 which featured UA coverage in the southeast at some of my local parts and I still have that issue to this day. Frankly, I credit that subscription to 4WOR to much of my passion for the off road hobby. The issue with Easter Jeep Safari in 2004 would have been my first exposure to Moab and it has been a bucket list trip arguably ever since.

When family vacation was planned for Park City, Utah this year I knew this was a prime opportunity to make that happen. Side bar – turns out I'll be driving from AL to Moab in October to ride co-pilot with a RZR crew. After some research, the plan was to leave Park City one morning, hit Arches National Park around lunch and then do a ride along Jeep tour with Twisted Jeeps. The next day we'd hit Canyonlands National Park and head back to Park City.
I pulled some strings at the airport and changed our rental car to a '23 Rubicon 4xE. I love my TJ, but man is the JL plush! The trip went exactly according to plan (shocker) and Twisted Jeeps was fantastic to do business with. Our guide, Jeeper Jeff, was a super cool dude and let me drive a few obstacles he technically wasn't allowed to. Here are a few pictures from the trip:

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That's great you got to make that trip out to Utah.
For me it was the Easter Jeep Safari VHS tapes I had in the late 90's.
Man that seemed like a cool area.
My first time out there was 2 Summers ago with Myrick and Jamin.
I loved every bit of it. The heat was worth the views for sure.
 
Yup those damn magazines had me hooked in too. That's a dying business and nothing to hook these young kids in now.
 
That's great you got to make that trip out to Utah.
For me it was the Easter Jeep Safari VHS tapes I had in the late 90's.
Man that seemed like a cool area.
My first time out there was 2 Summers ago with Myrick and Jamin.
I loved every bit of it. The heat was worth the views for sure.
I'd be lying if I told you those videos didn't make a little jealous. That looked like an absolutely epic trip. Total derail but I have to ask - is Jamin his actual name?

I've had some time to wrench on the TJ in the last few weeks and the JKS springs have been installed up front, trans cooler has been relocated and PS cooler was deleted. I stayed up late last night and replaced the intermediate steering shaft and reconfigured the upper rad hose to eliminate an air pocket. I'll post a full update this weekend after the JL shocks are installed and I get more road miles on it.
 
I'd be lying if I told you those videos didn't make a little jealous. That looked like an absolutely epic trip. Total derail but I have to ask - is Jamin his actual name?

I've had some time to wrench on the TJ in the last few weeks and the JKS springs have been installed up front, trans cooler has been relocated and PS cooler was deleted. I stayed up late last night and replaced the intermediate steering shaft and reconfigured the upper rad hose to eliminate an air pocket. I'll post a full update this weekend after the JL shocks are installed and I get more road miles on it.
Yes, we call him big lips also. He will answer to either.
 
Update time! Apologies for the long post, but I've been busy.

I swapped out the front Rough Country springs (intended for a 4cyl) and 2" spacers for 3.5" JKS dual rate springs without any issues. The JKS springs provided the same lift as the RC springs did with the spacer but made a substantial difference in ride quality. Crazy what the correct parts will do.

Before:

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While I was working on the front of the Jeep I just couldn't ignore the shiny JL Fox shocks that I picked up on Marketplace for $135 any longer and decided to swap those on as well. The inspiration for this swap came from this thread: https://wranglertjforum.com/threads/jl-shocks-on-a-tj.49036/
This is the front shocks in question: https://www.summitracing.com/parts/frs-985-24-171 I intend to swap rear springs and shocks when the D35 is pulled for the 8.8 swap. This was a pretty simple swap that took a few hours and some basic fabrication skills. The upper mount landed right at a factory hole in the shock tower, so I pulled a weld washer and shock tab out of my stock and ended up with this:

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Onto the lower mount. The original shock mount was removed to make room for the tabs needed to catch the lower eyelet. The lower mount ended up being a simple clevis that was attached with the LCA bolt.

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The tabs are meant for ½" hardware and the shock bushings are drilled for the foreign equivalent (aka 13mm), so I drilled the bushing out to ½" to work with the tabs and hardware I already had. I only had time to get the passenger side done this weekend but can already tell a positive difference in the on road ride quality. The difference will really become apparent once the rear axle is swapped and the track bar isn't trying to coexist with the fuel tank.

After:

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Next on the list was to spend some time on the cooling system to make it better than marginal. I've learned time and time again to start with the basics when troubleshooting and made something resembling a plan which was:
  1. Remove / relocate the power steering cooler.
  1. Relocate the transmission cooler.
  1. Revise the steering cooler mounting bracket.
  1. Install the driver side grill shroud between the grill and condenser.
  1. Revise the upper radiator hose to remove the chance of an air pocket.
I know that my cooling fan needs an upgrade (and that's coming) but I wanted to start the above list and see what happened. I unbolted the front grill shell and tipped it forward enough to get to the transmission and steering coolers. The transmission cooler was zip tied under the front bumper and the steering cooler was deleted for now.

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The upper radiator hose was reconfigured using a hose I'd originally bought for the Summit Racing radiator:

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The host fit the neck on the engine but was too large for the radiator inlet so I cut a piece from the old rad hose to act as a temporarily permanent spacer.The system was bled and I've driven it around town and to work one day and have noticed the a lower coolant temperature on the gauge. It is still running around 220* with the AC on full blast, which is higher that it should be but was able to maintain that temperature on the interstate which is an improvement. I'm also going to pull a page from Roadkill and drive it without the hood one day to see if a louver might help the issue. If nothing else it'll be entertaining, right?

The next step is to replace the existing radiator fan with a pair of 10" fans that can better keep up with the demand. Swapping to a pair of fans not only will increase CFM, but will allow a thicker fan since the water pump pulley will no longer be the limiting factor.

Another update that is completely unrelated to the cooling system was installing this Warn Zeon 8k winch that I picked up with a brush guard from, you guessed it, Marketplace. The brush guard is for a truck that I'm buying in the future and I managed to get the unit for less than the brush guard is worth – I'll take that all day! The Superwinch that it is replacing has been flawless for 10+ years now (and frankly, really didn't need replacing) but I've always wanted that Warn 'W' on the front of my Jeep.

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Quite a few, actually! I haven't made time to write my typical post, but here is the 15 second elevator speech:

Installed a pair of 10" Spal brushed fans that fixed my overheating issue. And by installed, I mean shoehorned.

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I'm also about 98% done with the 8.8 swap and have completed a fuel pump install. Having the tank out of the way made the axle swap a much more pleasant experience.

I used the Barnes 4wd truss and am a big fan of it, with the only issue being 100% my fault - I welded the shock tabs on backwards. More on that later. It is very common to relocate the stock spring perches to correct the rear springs bowing after the pinion angle is adjusted after a lift kit. Instead of relocating the stock perches, I clocked the truss so that the perches sit parallel at ride height, which also pulled the track bar out of the gas tank (they were previously trying to occupy the same space). While at it, the axle got a new pinion seal, outer bearings and seals, Powerstop pads and calipers with the TJ getting new JKS springs and factory bump stops.

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Back on the shocks - yes, even after installing the axle to check everything I didn't install the shocks and welded the brackets on backwards. I also discovered that with the shock brackets in the stock (ish) location the rear shocks are way too short - as in completely topped out at ride height (the springs won't settle enough to fix this problem). This presents an opportunity to make lemonade out of lemons and add a splash of your favorite brown water to it. Remember those JL shocks I bought earlier? Those are far too long to install in the stock location but would make a great candidate to go outboard with the rear shocks. I want to set this up to swap to a 12" travel shock in the future (these are 8" IIRC), but if I do this right I can temporarily (permanently, most likely) run these JL Fox units and move the tabs later to accommodate the longer shock.

The progress on the Jeep has stalled for a bit as I'm headed to Moab this Saturday for a week of wheeling with several RZRs. I was content to ride passenger and had told myself that I'd never own another SxS so I did the right thing and bought the cheapest XP1k turbo I could find out FB marketplace last week. I spent the weekend prepping it and my truck to make the drive.

I'll have plenty of time to write a forum post with the upcoming 48+ hours in the truck.
 
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Thanks for the update. This build always has me thinking about a 5.9L swap when my 4.0L in my 02 TJ kicks the bucket. I like how the 5.9L looks factory and keeps the factory gauges. Have fun in moab.
 
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