2008 JKU "Argenta" Build Thread (plus a 2010 Islander side project)

Never been but my wife and I were just discussing going there at some point in the near future. We'd probably pull the RV and make a week out of it. Still need to do a bit more research on the area as well as campsites, etc.

It gets fairly rural, fairly quickly, and I feel like we drove past a dozen or so state parks and campgrounds on the way back to I80, so I can't imagine you'll have too much issue finding a place that will work. As long as you "tow" something and can drop it, you'll be fine to get around the city with a truck too, though I will say, many of the roads, especially on Coal Hill, are SUPER narrow and tight. I got confused on one turn where the GPS said to turn left and I literally had to look out the window, essentially behind me, to see the street I was supposed to turn onto.

There are lots of museums, parks, monuments, etc. in Pitt that are easy to find and spend some time. There are also some historic neighboring towns, like Braddock, that have lots of history that you can literally park next to and explore (they did a cool job incorporating some of the abandoned steel mill machinery into the aesthetic and design).

Oh yeah, props to your son for rockin' the Sublime t-shirt!

He loves all thing 90's (my daughter does too)... they were born in the wrong decade! He had a Biggie shirt on in Cedar Point and had a few "great shirt" comments while waiting in line... :)
 
The JSS Exhaust should be here by Friday, so with any luck, I'll be making my first full engine warm-up and test drive by Sunday!

In the meantime, I spent a lot of the weekend wrapping up the smaller items, starting with the EVAP system:
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My diagram of what the system should look like... I had to do this because the MB supplied instructions were not only awfully written, they were wrong...

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All the connections at the top of the MB tank are easily accessible via the MB cutout panel..

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My DIY EVAP relocation... everything sits above the rear axle and hopefully will clear without any unnecessary bumpstops needing to be added. I tried to reuse some of the OEM hoses and QD fitting. Everything is essentially the same, the major change being the location of the charcoal canister itself, as well as the vent. I didn't even need to extend the wiring, which was a plus...

Filling the 8HP can be a pain, but I had a brilliant idea to use a handpump and push it in from the cooler return line:
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Unfortunately, since I'm using the JL392 cooler lines - which have a built-in thermostat - I needed to do a few extra steps. Using a heat gun, I had to constantly put some heat on the thermostat block, while my son slowly pumped in ~6 additional quarts:
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It's not crazy if it works, right?? The block seemed to open fully at about 128F, but continually cooled down to ~105F when fluid started getting pump through. As long as I kept steady heat on the block, it kept flowing.
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While I was working underneath, I also installed the B&M T-case shifter. Good news for those wanting to do an 8HP swap - the B&M t-case bracket fits perfectly and no modifications are needed (seen here next to the modified Ram 1500 t-case bracket):
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After installing the B&M cable and securing some of the trans wiring while I was over there, I installed the Adam's Driveshaft from t-case yoke and 1350 CV shaft. Unfortunately, there was a small bit of interference on the Ram 1500 8HP rubber mount:
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I chopped off the small lip above that was hitting the CV "barrel", and then also installed 1/4" spacers above the mount to give some extra clearance. At the moment, I have full CV range of movement without any interference!.
 
This was a busy week of wrapping up small things, like the small drip on the one trans cooler fitting, securing the fuel hoses, installing exhaust, etc.

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But after hours of checking and double-checking small details, confirming PID’s, burping the cooling system, checking everything for proper torque and leaks, and then some - we had a successful first drive!


I could not be happier with how she feels, sounds, and looks! The power is amazing and I’m barely giving it any throttle. The transmission is ridiculously smooth and works exactly as you would want.

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There are a few kinks to work out: my traction control light is coming on periodically. Not sure if it’s related to the slightly off center steering wheel or a wheel speed sensor misalignment, but I’ll need to fix the steering wheel alignment either way.

As it heated up, the driver side rear brake backing plate started to touch the rotor. I’m not sure if it’s just the heat warping it enough to touch the rotor, but I bent it back with my hand and that helped for a few minutes, at which point the noise came back although less prominent. I will need to pull the wheels and check stuff anyways, so not likely a big concern (plus I still need to zip tie the rear sensor wiring to the control arms).

I ordered some proper exhaust hanger hooks to replace the temporary ones I am using. I will also need to slightly trim the transmission crossmember bracket on the frame as the catalytic converter is ever so slightly touching it (and I can’t move the downpipe over any more!).

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I took my son for a ride after the initial solo ride and that kid was giggling more than I was 😂 I asked if he wanted to Hemi swap the Islander before getting his STi project car and he quickly said “yeah we may have to!”… thataboy!
 
Had to take a small break from Jeep work to take a father-son-only trip to EAA AirVenture in Oshkosh. My son is a big aviation fan and wants to eventually work in the industry. So, with that, I try to give him experiences that will keep the passion alive and give him some insight as to what specific part of the industry interests him the most...

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Leo suffers from ADHD really bad (I do too), but he's developing mechanisms to maintain his grades and keep his assignments straight. As a result of being just 1 point shy of having an "A" average for this past year, I treated him to a flight on the Ford Tri-Motor, which was totally worth the money and worth the long wait in the heat.
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He was a little woozy after the flight - which started before the flight (he had a stomach bug that he was fighting as we got off the plane in Chicago).
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Not every day you get to take a short nap under the wing of a DC-3!
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Seriously, how does a 2.0L Turbo Wrangler only get 17.6 mpg on flat-a$$ Wisconsin roads with the windows up and A/C on low? My 6,600 pound Wagoneer with a 400hp Hemi with 5 adults and 4 suitcases got 23.4 mpg driving across I-80 through PA, OH, and IL!
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After a successful first drive (actually, first driveS), it was time to address some of the idiot lights on the dash...

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The ABS/Angle Sensor was a quick fix - just a matter of straightening the wheel by adjusting the drag link (I got it closer, but still need to tweak it). The RH Side Satellite Acceleration Sensor was my mistake - I (or my son?) must have unplugged it when attempting to unplug the door wiring. Plugged that in and the airbag light turned off... (y)

I did a few miles of cruising and the EBD/Trac lights turned off and everything is working as it should!

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The brakes worked great but felt crappy. Now that the engine is running, I decided to bleed the ABS and brakes one more time, this time using the booster to give some extra push. This did the trick - I got a massive air bubble on the driver-side rear line. After that, the brakes feel better than factory and stop amazingly well.
 
Working on adding "Sport" mode to the transmission...
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The PCS controller has a simple USB cord that plugs into any Windows PC and is readable/writable via the PCS TCM2800 software...

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The software is easy to use and I'll include a write-up on my Hemi Swap page, but everything went smoothly and Sport Mode (aka "Calibration B") is a bit more aggressive than a Ram/Wagoneer "sport" mode, with measurably firmer shifts. Overall, great for daily driving on a rig with big tires and in hilly terrain.
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With the software figured out and switch confirmed operational, I am now working on fitting the JSS "console adapter" and need to find a good place to mount the switch. The skies opened up so more pics to come...
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Been chasing a few small leaks in the fuel filler hose since converting to the Motobilt Rear Tank setup. Luckily, some Jeep Angel on Facebook posted about a quick and easy fix:
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I got mine from O'Reilly's and it should be here today. With luck, this will completely fix that small gas smell and fuel leak I get when refueling (we're talking just a few drips during a full fill up, but enough to make it stinky).

Items on my to-do list for this week include...
  • Clearance trans x-member for catalytic converter
  • Install exhaust hangers
  • Zip tie front accessories better
  • Install bump stops
  • Install inner fenders
  • Wire in sport switch for trans
Some longer term items I need to order some parts for are:
  • Make air damn panels in front of grille
  • Install interior floor insulation from large DEI panel
  • Install new carpet
  • Find some sliders
There's a guy new Philly that has a nice set of Poison Spyder sliders and I wanted to pick them up last weekend, but my daughter's college move-in took way longer than I thought (we were short 1 helper who had a death in the family) and the weather wasn't cooperating. Speaking of the move - it was a good opportunity to keep an eye on how the Hemi in the Waggy runs with a trailer and some additional load. Basically... it didn't change anything.

It was in the low 80°s and humid during the hottest part of the drive. The coolant temps never got higher than 215°F, and the trans temp never broke 180°F, even traveling at 70-75 MPH on the PA Turnpike. Gas mileage sucked - dropping down to just under 13 mpg, but it truly felt like nothing was back there, even up the long hills. The 8HP75 does a real nice job keeping the engine happy and always in a spot where it's working efficiently.

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This matches my experience and temps in the JKU as well. I rarely get above 174°F on trans temps, even when working the transmission as hard as I can around these country roads and hills. My engine temp is basically at 208°F about 90% of the time. It will briefly hit 211°F up the long, winding road from the next town over, which Google Earth says is a ~750 ft elevation gain in about a mile and a half:
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If my math is correct, that's about a 8.75% grade. This makes me fairly confident that I'm not currently having any air daming issues and I'm getting proper flow from the fans. I still am going to install/modify/make some panels to fill in the spots to the sides of the radiator to ensure that I'm not getting any errant air flow around, plus I still need to install the inner fenders, but at least I'm not fighting temps at the moment (which would be indicative of other issues!).
 
The Precision FNH106 fuel filler hose arrived. It appears as though it fits some Toyota models, and maybe a Pontiac or two. But, regardless of that, it fits perfectly! I haven't filled the tank yet but it is perfectly sized on both the tank and the filler neck, so I can't imagine I'll be having any leaks at this point...
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With the fuel leak eliminated, I thought it was safe to finished welding up the exhaust and adding some hangers. The good news is that I was able to thread the needle a bit and get the cat about 1/16" to 1/8" off the transmission crossmember, so no need to do any cutting or trimming there...
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With the exhaust wrapped up, I'll give the manifolds one last torque check and then work on bolting the inner fenders on...
 
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Good news, the new fuel filler hose worked flawlessly - no leaks, no smells, and no rubbing 👍

I got the Sport Mode switch fully wired in. I had to switch the PCS digital input to “high”, so that I could trigger with 12V+ instead of 12V-. Doing so let me wire the switch up to illuminate when pressed, giving a clear indication that Sport mode is on.
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I decided it was time to do a highway run. Thankfully, the Jeep ran flawlessly, with temps never exceeding 211°F. Everything felt smooth and handling is as expected. Cruise control worked exactly as it should, with +\-\Res working just like stock.
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Next up - time to get those inner fenders installed tomorrow!
 
Football camp started up, which means school isn't too far behind. I'll be getting really busy again in a few weeks until late November, so I'm trying to get as many things wrapped up as humanly possible. The Islander needs some love, so I figured no better time than now to get moving on it...

First up was to get the carpet pulled out and see how bad the floor rust is. After inspecting everything, it looks like the drivers floor is the only place with rust. I can't explain it - there isn't any rust on the frame, torque boxes, or anywhere. I wonder if it was just a combination of leaking top, combined with some salt residue (from winter) over time, meeting up with some surface rust from below? Seriously, I have no idea - this was the only spot I could find anything:
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Since I wanted to pull the entire carpet out to do a full inspection, I decided to give it a deep power wash. I gave it a soak with some dilute degreaser and then some lavender scented Fabuloso, then scrubbed with a stiff bristled brush:
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After soaking, scrubbing, soaking, scrubbing, and repeating a few more times, I turned to the power washer:
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When these dry, I think I'm going to install them in the Silver JKU since I need a few weeks to get the Islander all fixed up. Besides the floor, I have been getting two O2 sensor codes on the passenger side, so I'm guessing I need a set of manifolds. I also want to swap out the Pypes exhaust for a quieter muffler (it's just annoying sounding on the 3.8L, esp as it does its best to climb mountains nearby). When the Islander is all fixed up, I'll just buy a new carpet kit for it.

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[275's on a set of OEM Ram 2500 chrome wheels (with ~6.5" backspacing)]

I may need to find an alternative set of fender flares, even if just temporary. The KBD's look great but the guy I go to for my annual PA inspection said that there was no way he could "let these slide". I said I have a set of "rollers" that don't stick out as far, but he said that there's not enough coverage on the front of the flare. So I may need to find a crappy set of flares that come out further in the front. I absolutely hate the "batman wing" look, but it may be my only chance. I'm not too worried long term, as I'll simply swap the tires and flares out every June to do a clean and get my inspection done.
 
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