SilicaRich's Overland TJ Rubicon Build

[SilicaRich]

Hey great looking tj! I was wondering how much lift and what tire size you are running hoping to lift my tj this summer and I like the way yours sits.
Thanks
Chad

Appreciate it Chad

I order an HD OME lift through DPG:http://dpgoffroad.com/products/old-man-emu-ultimate-tjlj-wrangler-kit/ (I ordered the kit without the BL and MML)
Overall lift was about 2.5" after break in. It's a good platform in case I ever want to go to a larger tire again. I highly recommend calling Dirk at DPG to make sure you get exactly what you want. My tire size is 255/75R17 or approximately a 32"x10" tire.

 

[Roc8man]

An old idea that I have brought up in past posts. I've been sitting around and really thinking the last few weeks and have decided to make an executive decision on the Jeep when the time and money presents itself. I will be doing the Cummins 2.8l Repower Kit.

Why the decision? I want something with plenty of torque, easily tunable, simple design, and can get solid fuel milage. Theoretically the cost of the kit by itself will probably be around $10k alone (praying that it's cheaper), however an additional $1k-1.5k (not including potential labor costs) will be added as I will ditch the current NSG370 6 speed transmission in favor of a 5 speed NV4500. Why ditch the 6 speed? The transmission is a good little transmission for what I use it for but it does not have a high torque rating (incase I decide to tune the 2.8 in favor of more power) and is stupid expensive to repair, not to mention difficult to get parts for. The NV4500 is a proven reliable transmission, cheap to repair, higher torque rating, easy to build up, high OD (perfect for hitting the sweet spot on a low rpm loving Cummins), and bolts up to just about anything. I have a decent amount of prior knowledge dealing with the NV4500 while searching for one for my old FJ40.

Now there's the idea, "That's a $15k investment that will never pay for itself. Sell the Jeep and get something else". Truthfully, I'm not in it with the expectations that it will pay for itself, my Jeep is already an investment that will never pay for itself and I don't intend on getting rid of the Jeep. That being said I did some general math with the investment being paid off in about 15 years. I bought this giant Lego set of a Jeep to modify and make me happy, and this swap will make me happy. We are talking about incredible fuel range, averaging say 26 mpg that's almost 500 miles on my standard fuel tank not including a spare 5-10 gallons of extra fuel being carried. That just tripled my range. That means less time focused on my fuel gauge and more time enjoying the views and adventure.

Let me know what yall think and feel free to express your opinions, good or bad. I will always be partial to the 4.0 but I feel that for the sake of making the Jeep superior to my standards, this is the route I should take. In the meantime, it's time to start saving up and get a job over the summer.

I don't know of anyone who modifies their vehicle(s) in the name of "investment". We all do it to get it to the level we want to make us happy. There is no poor decision if you are happy with it after you've spent x dollars on it. When my TJ 4.0L cracked a piston skirt off into my oil pan, I made the decision to "upgrade" the engine to something that would make me happier. I looked at Cummins 4BT, Stroker kit and SBC. In the end, I decided I wanted to "upgrade" the power with an LS3/6L80 combo. I love it and would do it again. I am constantly smiling when I drive my Jeep. That's why you do it. Not to get "approval" or opinions from others. I love the idea of having significantly better mpg and still plenty of torque. In the end, I preferred the much lighter weight of the 6.2L with 6L80 (lighter than what came out of my TJ) but with more torque than the Cummins and a lot crappier mpg. Please let everyone know what YOU decide and then do it. You will never regret doing something to make you happy...

Best of luck,
Dave

 

[SilicaRich]

I don't know of anyone who modifies their vehicle(s) in the name of "investment". We all do it to get it to the level we want to make us happy. There is no poor decision if you are happy with it after you've spent x dollars on it. When my TJ 4.0L cracked a piston skirt off into my oil pan, I made the decision to "upgrade" the engine to something that would make me happier. I looked at Cummins 4BT, Stroker kit and SBC. In the end, I decided I wanted to "upgrade" the power with an LS3/6L80 combo. I love it and would do it again. I am constantly smiling when I drive my Jeep. That's why you do it. Not to get "approval" or opinions from others. I love the idea of having significantly better mpg and still plenty of torque. In the end, I preferred the much lighter weight of the 6.2L with 6L80 (lighter than what came out of my TJ) but with more torque than the Cummins and a lot crappier mpg. Please let everyone know what YOU decide and then do it. You will never regret doing something to make you happy...

Best of luck,
Dave

Appreciate the input Dave.

Speak of the devil, I am currently deciding on my transmission for the swap (discussion thread on Wrangler Forum). I initially said I was considering the NV4500, however it sounds like that might require some relatively serious cutting for fitment. Then I considered the NV3500 but immediately remembered the cousin of the 3500, the NV3550 which was offered in the TJ from 2000-04. There's also the AX15 from 99-97 TJs priced nearly the same as the NV3550 but the 3550 has a slightly better OD and granny gear. Currently still weighing out my options but really leaning towards the NV3550 currently. I'm not sure but I believe the only minor hiccup I would encounter while swapping in the NV3550 is possibly installing new transmission mounts. Any input to confirm or deny that would be awesome. I could also buy and swap the transmission prior to even buying the crate engine.

And just for fun I thought of the LRA aux tank that adds about 12 extra gallons. Just kind of toyed the glorious idea of having 31 gallons of fuel matched say to a conservative 20 mpg out of the Cummins for 600+ glorious adventure filled miles without worrying about filling up. That not including an extra 10-20L of fuel in Jerry cans. But that's just a fun thought to chew on at this point. I still need to save up and do the swap.

 

[SilicaRich]

Itinerary For Transmission Swap

After a little discussion on Wrangler Forum my two transmission choices have pretty much been narrowed down to the NV3550 or AX15, both at which are nearly a direct bolt in swap. The only hiccup with the AX15 is getting the transmission paired to the 241 Rubi T-case, appears I would need to replace the input shaft on the transfer case. At this point, I'm a solid 70% sure the NV3550 is the perfect transmission to swap in. So enough talk, here are some numbers.

-Transmission (NV3550 core): $1000
-2000-04 TJ Flywheel: $50
-2000-04 TJ Luk Clutch kit for NV3550: $90
-NV3550 Shifter Assembly: $90-$120 (probably won't do short throw, thats extra $$$)
-Core Charge: $300 (I'll explain why I'll likely pay the core charge without sending in my 6 speed)
-Possible Miscellaneous: $200
-Installation: $0 (more than possible to swap in over the coarse of a weekend in our barn)

Total Approximate Cost: $1730-$1760

Now to explain why I would likely pay the core charge and not send in my 6 speed. My particular NSG370 was only offered from 2005-06. The NSG370 currently used in JKs is NOT the same, the JK version is over an inch longer in length. I did a little research, 05-06 NSG370s new and reman cost between $3000-$4000. Assuming the swap occurred this winter, that would put my transmission at around 70k miles with only 30k miles on the shifter assembly and clutch kit. That would give me no reason to post the transmission for sale at $2500 and take no less than $2000. Boom, transmission swap just paid for itself and more. Now all that being said, it is more or less just a good theory. The point being is that I should be able to recover a lot of my money spent by selling my NSG370 transmission rather than send it in to recover a $300 core charge.

Here are some numbers regarding how the NV3550 would do paired with the Cummins 2.8 and my current drivetrain:

Speed: 70mph (chosen as my average highway/interstate cruising speed)
Axle Ratios: 4.10
5th gear: .78
Tire Size: 31.77" (255/75R17 ST Maxxs actual diameter listed on Cooper's website)

Final Cummins 2.8 RPMs: 2369 RPMs

Considering the 2.8's power band of 1500-3000 RPMs, this does put me at the higher end of the band but should yield a solid combination of performance and fuel efficiency. Now lets address the elephant in the room. Clearly I'm overgeared, that is no doubt obvious. However, due to my consistent indecision with tire sizes I will likely choose not to regear, at least for a while. If push came to shove, I'd likely be more willing to upgrade to a taller tire than regear.

Thought yall might appreciate some good numbers and information. I've been really thinking about this swap the last few weeks and really wanted to start digging into the reality of the swap starting with the transmission. Really apologize about how stagnant this build has become, beyond just adding mods I need to actually get the Jeep out and about exploring.

Here's to future badassery!:friday:

-G

 

[gixxerphil]

After a little discussion on Wrangler Forum my two transmission choices have pretty much been narrowed down to the NV3550 or AX15, both at which are nearly a direct bolt in swap. The only hiccup with the AX15 is getting the transmission paired to the 241 Rubi T-case, appears I would need to replace the input shaft on the transfer case. At this point, I'm a solid 70% sure the NV3550 is the perfect transmission to swap in. So enough talk, here are some numbers.

-Transmission (NV3550 core): $1000
-2000-04 TJ Flywheel: $50
-2000-04 TJ Luk Clutch kit for NV3550: $90
-NV3550 Shifter Assembly: $90-$120 (probably won't do short throw, thats extra $$$)
-Core Charge: $300 (I'll explain why I'll likely pay the core charge without sending in my 6 speed)
-Possible Miscellaneous: $200
-Installation: $0 (more than possible to swap in over the coarse of a weekend in our barn)

Total Approximate Cost: $1730-$1760

Now to explain why I would likely pay the core charge and not send in my 6 speed. My particular NSG370 was only offered from 2005-06. The NSG370 currently used in JKs is NOT the same, the JK version is over an inch longer in length. I did a little research, 05-06 NSG370s new and reman cost between $3000-$4000. Assuming the swap occurred this winter, that would put my transmission at around 70k miles with only 30k miles on the shifter assembly and clutch kit. That would give me no reason to post the transmission for sale at $2500 and take no less than $2000. Boom, transmission swap just paid for itself and more. Now all that being said, it is more or less just a good theory. The point being is that I should be able to recover a lot of my money spent by selling my NSG370 transmission rather than send it in to recover a $300 core charge.

Here are some numbers regarding how the NV3550 would do paired with the Cummins 2.8 and my current drivetrain:

Speed: 70mph (chosen as my average highway/interstate cruising speed)
Axle Ratios: 4.10
5th gear: .78
Tire Size: 31.77" (255/75R17 ST Maxxs actual diameter listed on Cooper's website)

Final Cummins 2.8 RPMs: 2369 RPMs

Considering the 2.8's power band of 1500-3000 RPMs, this does put me at the higher end of the band but should yield a solid combination of performance and fuel efficiency. Now lets address the elephant in the room. Clearly I'm overgeared, that is no doubt obvious. However, due to my consistent indecision with tire sizes I will likely choose not to regear, at least for a while. If push came to shove, I'd likely be more willing to upgrade to a taller tire than regear.

Thought yall might appreciate some good numbers and information. I've been really thinking about this swap the last few weeks and really wanted to start digging into the reality of the swap starting with the transmission. Really apologize about how stagnant this build has become, beyond just adding mods I need to actually get the Jeep out and about exploring.

Here's to future badassery!:friday:

-G

Hey Guthrie,
You may want to look into the AX15 over the NV3550. I see a lot of talk about NV rebuild kits being junk b/c that company is no longer in business and the parts are Chinese. I have the NV3550 and it's been great with 200+K on it, so I won't bad mouth it.
I've also read about an AX15 called "The Terminator".......I believe it's an AX15 on roids

 

[SilicaRich]

Hey Guthrie,
You may want to look into the AX15 over the NV3550. I see a lot of talk about NV rebuild kits being junk b/c that company is no longer in business and the parts are Chinese. I have the NV3550 and it's been great with 200+K on it, so I won't bad mouth it.
I've also read about an AX15 called "The Terminator".......I believe it's an AX15 on roids

I would have to check with the cost to replace the input shaft on T case in order to pair the AX15. That cost would probably fall in that miscellaneous cost I put above. The cost served more or less as a precautionary cost that would either be added, subtracted, or something in between to the overall cost. Best thing to do would be to call Novak or Advanced Adapters and have them tell what I need. While talking to them, I might bring up the quality of newer non-NV3550 parts and get their opinion on them. That being said, they seem to really favor the AX15 on their website. Everything else should bolt right up. Overall cost difference between cores should be nearly the same. I've found AX15 and NV3550 cores (fully rebuilt and upgraded) for as less as $900 but I'm thinking about trying to see if I can find a "new" AX15 or NV3550 for a reasonable price. Apparently there is a lot of overstock of both transmissions.

Only thing I will say in regard to not considering the AX15 over the NV3550 is that people still love to buy rebuilt NV4500s (made by the same company). I would venture to guess that if rebuild kits for the 4500s are still a quality product why wouldn't 3550 rebuild kits not? A lot of questions to answer and a lot more research to do.

 

[gixxerphil]

Only thing I will say in regard to not considering the AX15 over the NV3550 is that people still love to buy rebuilt NV4500s (made by the same company). I would venture to guess that if rebuild kits for the 4500s are still a quality product why wouldn't 3550 rebuild kits not? A lot of questions to answer and a lot more research to do.

I honestly have no clue. I've got a little over 200K on mine and have no complaints. I'm just passing along info I've read on other threads

 

[SilicaRich]

Transmission Decision and 2nd Half of the Year Plans

Nothing new has really happened since last discussion regarding my transmission choices besides making the decision to go with the AX15.

Reasons:
1. Surplus, surplus, surplus! They made more of these transmissions than they installed so brand new transmissions are still available. https://www.novak-adapt.com/catalog/transmission/transmission-packages/ax15-package/
2. Aisin Warner is still in business and new parts are not Chinese made
3. Easily built up if necessary

Only concern I still have regarding the transmission is getting it paired to my 241 Rubi case. I plan to call Novak and ask when I order the transmission. I have enough saved from working this summer with a survey crew to purchase the transmission now, however, with my fall semester closing in I plan to order the transmission just prior to returning to Texas in the winter. I should be able to recover some of my loses selling my current transmission and will continue to work over winter break to bring in extra cash.

So first step to the swapping in the Cummins is officially planned. Some news I have heard about the Cummins 2.8 Crate Engine Kit from an unreliable source is the price quoted for a guy at Jeep is $5000 to have the engine swapped in his JK. That price seems kind of BS especially if that includes labor but we shall still see. Cummins is closing in on 4 months overdue on releasing the kits and their price. Also have a friend from work that said he would be willing to do the swap for me for a reasonable price.

Current status of the Jeep. Runs fine with zero issues besides a water leak coming from one of my seals where the liftgate seats. Joy. Ordered new weatherstripping to replace the old, fingers crossed it solves the issue. Tired of the Jeep smelling like wet dog. Still have a bunch of other accessories to install that I haven't gotten around to doing due to no motivation to tackle this heat especially since I deal with it every day at work.

Accessories still needing to be installed:
1. Tuffy Center Console
2. LightForce HIDs
3. VIAIR Compressor

That's pretty much it, an update with nothing really done.

-G

 

[FireJeep]

Great thread, I have thoroughly enjoyed reading it!!! I have a 2005 Unlimited Rubi. and am very happy with it. I bought the DPG OME kit 12 years ago and have been pretty happy with it so far. My issues with it are as follows: Right front shock (hydraulic back then, they have since upgraded to what you have) blew after 5 years the others were fine. I replaced all four with Bilstein 5100 and am pretty happy with the performance. The JKS front track bar is junk, the spherical joint at the frame end froze up despite being greased regularly. It took me quite a while to figure out what was making all the noise in the front suspension (I thought it was control arms, then I thought the cam bolts that hold the control arms....geez....). I bought a Metalcloak front track bar and am very happy with it so far, much heavier duty and very simple design. The springs have held up well but the paint/powder coat did not, pretty much junk. I have come to the realization that powder coating is great if you never take something out into the elements. once it gets a small nick, moisture gets behind and wreaks havoc on the base metal and the remaining powder coat. I think I will stick with POR 15 and the like instead...... My next mod is going to be metalcloak front midline fenders, along with rear armor, this will allow this lift to run 35" tires, keep center of gravity low and allow for some really nice articulation.....
Love your TJ, looks good, part of your mpg issue, I believe, is your roof rack, jeeps already have the aerodynamics of a barn door, but that rack just made it that much worse.... just my opinion....I pick up my M416 trailer on Tuesday, I can't wait!!!!!

 

[SilicaRich]

Great thread, I have thoroughly enjoyed reading it!!! I have a 2005 Unlimited Rubi. and am very happy with it. I bought the DPG OME kit 12 years ago and have been pretty happy with it so far. My issues with it are as follows: Right front shock (hydraulic back then, they have since upgraded to what you have) blew after 5 years the others were fine. I replaced all four with Bilstein 5100 and am pretty happy with the performance. The JKS front track bar is junk, the spherical joint at the frame end froze up despite being greased regularly. It took me quite a while to figure out what was making all the noise in the front suspension (I thought it was control arms, then I thought the cam bolts that hold the control arms....geez....). I bought a Metalcloak front track bar and am very happy with it so far, much heavier duty and very simple design. The springs have held up well but the paint/powder coat did not, pretty much junk. I have come to the realization that powder coating is great if you never take something out into the elements. once it gets a small nick, moisture gets behind and wreaks havoc on the base metal and the remaining powder coat. I think I will stick with POR 15 and the like instead...... My next mod is going to be metalcloak front midline fenders, along with rear armor, this will allow this lift to run 35" tires, keep center of gravity low and allow for some really nice articulation.....
Love your TJ, looks good, part of your mpg issue, I believe, is your roof rack, jeeps already have the aerodynamics of a barn door, but that rack just made it that much worse.... just my opinion....I pick up my M416 trailer on Tuesday, I can't wait!!!!!

Dirk actually told me that JKS made slight changes unded the radar to their track bar about 4 years ago due to flaws like you mentioned. Appreciate the kind words.

Honestly I would have thought the same about the mpg issue if I had not have taken the mpg hit prior to installing the rack. I went from consistent 16-17 mpg highway on 33×12.5 tires and big bumpers to 11-13 mpg highway when I went to 33×10.5 tires. Now with the rack I get 10-12 mpg on 32×10" tires. I expected a 1 to 2 mpg hit when I installed the rack but something went wrong prior to its installation, possibly fuel filter or exhaust leak (about to explain).

Update: So I got in a 4 car fender bender two weeks ago on my way to class. Basically in stop in go traffic, I was rearended and went into the car in front of me. Turned out the person who caused it was behind the car that hit me. No structural damage or cosmetic damage to the Jeep's tub or frame, drives straight with no issues going 65mph. Only thing damaged was one of my IPF 968 offroad lights on the front bumper. Cracked housing and lens cover which will be replaced by the driver at fault. Other cars in the wreck came out much worse looking than me, Ill post pics later. Car in front will likely need its rear liftgate replaced from my front bumper and the car behind me had serious damage to its bumper and hood from my tire carrier and hitch.

So other issues, I have noticed a goofy squeal when I turn off the Jeep or when its close to stalling for about a year. These only occur once the Jeep is warmed up. I also hear the squeal when I am going over uneven surfaces with the front end. Initially I thought it was a belt or pulley on its way out but didnt think much of it until it started to squeal louder when the Jeep was turned off or driving on uneven surfaces. While trying to pinpoint the noise thinking it was coming from one of the pulleys I realized it was coming from somewhere in the general area of the throttle body making me believe the manifold gasket is possibly failing, would explain why the noise occurs when the Jeep is hot. Could also explain goofy idling at times when the Jeep is hot. Plan to take her to my favorite shop here in Fayetteville in the morning and see if they can give a more specific diagnosis.

Oh and some good news! The liftgate no longer leaks. Just had to replace the upper liftgate seal.

 

[SilicaRich]

I believe the squeal has been officially been found. I have a vacuum leak coming from a near dead vacuum elbow just under the throttle body. I bought a pack to replace the elbow at the parts store this morning but they dont fit properly so I plan to go ahead and order a brand new vacuum harness to replace it all. This might be possibly the culprit of my mpg issues. Possibly a vacuum leak that has progressively gotten worse over the years.

I talked with a Cummins rep via social media last week regarding their Repower program and its woes. He mentioned that all beta engines are sold and currently being refined. This includes installation, kit parts, etc. Basically implying that Cummins was to get this right the first time around. He apologized for the long delay regarding its release and understands everyone's frustration. They just want these kits to be damn near perfect. However, the Repower kit is looking more and more like a dream than a reality if the projected prices are correct which may cause me to have to boot the idea. It is frustrating for me to think of giving up on the idea of making the Jeep Cummins powered but if prices are what is projected then they are nowhere near going to be close to what the community was hoping for. For that reason I plan to bring back up the Cotybuilt 1.9L VW TDI swap as a back up plan. Already proven engine, already proven swap, and the starting cost is just under $6k. Again, still a back up plan.

Now fun news. I will be attending the Ozark Rendezvous October 20-22nd in Ozark, AR. I have been trying to line up events with my schedule and finally have found one perfect for my schedule and is only an hour drive away from me. It is going to be a long month anticipating

 

[SilicaRich]

Best News in a While

So I guess all I had to do is threaten to do a different swap?

This is a post from a Fred Williams on Instagram. He is currently travelling with the famous 2.8 swapped TJ named Tubesock (the one they submerged for 30 minutes and busted the oil pan of the 2.8 with) and a Cummins reps so this could be very reliable information for what Cummins plans to list this kit as.

Taking the Jeep to a shop in the morning to try and diagnose the squeal. I am 100% it is some sort of leak around the throttle body or possibly the exhaust manifold but I can't narrow down the exact spot. I know for sure however, that it is not a vacuum leak after doing several more tests.

 

[SilicaRich]

Squeal officially dianosed, throttle body gasket and a worn idle control valve. I guess I about nailed the diagnosis on the head. Should have the Jeep back by tomorrow at the latest

 

[SilicaRich]

Getting the Jeep back today, throttle body gasket was definitely sucking air in the wrong places and was replaced. They also diagnosed that my AC compressor is definitely dying internally, something I was relatively aware of with the howling it has been making the last 3 years. Tech recommended to run the compressor till it dies, if it actually dies, quoting me $1200 for replacing the entire AC system with a warranty. Meh who needs AC anyways when you can roll down your windows or better yet remove your doors

Also ******* news regarding the wreck that I forgot to mention. My adjuster was taking too long to contact me so I contacted them only to find out that the driver at fault of the wreck is uninsured meaning there is no way for me to get compensation for my damaged lights without a claim. If I understood everything correctly, that would end up resulting in spending far more than the lights are worth and only increase my rates. Very unfortunate for the other two vehicles involved in the wreck. This means I will not be getting replacements for my lights, however, I do have the two sets of LightForce lights that I have been so lazy to install that will do fine. Might possibly invest in some cheapo Chinese lights (less than $100) to compensate but we will see. Probably will sell the old lights for cheap to compensate a little.

 

[AggieOE]

Getting the Jeep back today, throttle body gasket was definitely sucking air in the wrong places and was replaced. They also diagnosed that my AC compressor is definitely dying internally, something I was relatively aware of with the howling it has been making the last 3 years. Tech recommended to run the compressor till it dies, if it actually dies, quoting me $1200 for replacing the entire AC system with a warranty. Meh who needs AC anyways when you can roll down your windows or better yet remove your doors

Also ******* news regarding the wreck that I forgot to mention. My adjuster was taking too long to contact me so I contacted them only to find out that the driver at fault of the wreck is uninsured meaning there is no way for me to get compensation for my damaged lights without a claim. If I understood everything correctly, that would end up resulting in spending far more than the lights are worth and only increase my rates. Very unfortunate for the other two vehicles involved in the wreck. This means I will not be getting replacements for my lights, however, I do have the two sets of LightForce lights that I have been so lazy to install that will do fine. Might possibly invest in some cheapo Chinese lights (less than $100) to compensate but we will see. Probably will sell the old lights for cheap to compensate a little.

Man that sucks as far as insurance goes. I 100% agree though that buying them again will be cheaper than going through insurance. I learned that the hard way on our old Escape: $1200 repair vs $100/mo rate increase for the last two years. I'm saving insurance claims for only big claims now.

As far as the AC goes... shop around on price. One place replaced the Compressor and Dryer on my previous Boss 302 for $1,600. Later, I had the compressor and dryer replaced on the Escape for <$700 at a different place (smaller one-off company). Obviously, the second place didn't use OEM Ford parts but does it really matter, maybe, idk. Both came with 12-mo warranties though.

And i think it goes without saying... +1 for the Cummins idea. lol