[Chs32]

I've just about completed a full bottom end swap of front and rear axles off a rubicon, along with the transfer case, into a 1997 TJ. Its taken a long time, even though I hired someone to do the heavy work of the axles and transfer. However, I did have lots of issues to resolve along the way and thought I'd share some of the problems and resolutions.

I picked up the complete bottom end of a 2003 Rubicon, front and rear axles, shafts, pumps, and T-case, off of Ebay for about $3800. Shipping was another $500.

The axles and case can be a straight bolt in for the most part. In my case, I already have a 2" body lift and a 4" suspension lift and this added some other problems, but also resolved issues.

The first big problem was that I have an automatic transmission. The 241 case has a much shorter post extending to the seal of the transmission than the 231. I read that you could purchase an extender from teraflex and I did. However, that extender was also too short. Ultimately I used that as a guide to having a custom extender made by a local machine shop. I don't think this is needed for a manual.

I also installed a new CV rear shaft from Tom Woods. This required a large rotation of the rear axle to point the pinion at the T-case. With the large lift, we had to cut off the axle attachment brackets and reposition them, along with the sway bar bracket, in order to get the necessary rotation without binding. We replaced the upper control arms with adjustable arms to get the rotation we needed. This also allowed us to remove the t-case drop of 1" that was put in with the lift kit.

Although I had the stock rubicon front shaft, it was not the correct length. Rather than having it adapted, I also replaced the front driveshaft with a custom shaft.

With the existing 2" body lift, the 241 case went right in. I had read that the fit was very tight without a lift and could require modification. We had no problem.

The emergency brake cable must be replaced with a rubicon cable. You do not need to replace the proportioning valve.

I'm still wrapping up the electrical issues on my own. The speedo connector is slightly different on the 97, with round pins instead of flat pins. I purchased new connectors from www.partsyouneed.net for this, along with the connectors for the axle locker indicator lights and the connector for the 4-wheel drive switch in the new transfer case (its different on the 241). I found the wiring online and will try to find the thread again. Teraflex also sells this connector and the wiring colors are included.

I did a lot of research on the wiring for the stock rubicon pumps. Bottom line, ignore the pink, black to ground, red to power. Do not power the pink or you will blow the pump. It is used to provide feedback to the rubicon computer and isn't needed on the TJ swap.

I'm just about finished with the electric. I'm installing two safety switches and two indicator lights in the panel. The switches will power up each pump. The lights are wired by running power to the light, then running wires to each axle, from the light to the axle, the second (return) wire to ground. When the axle locks, it completes the ground circuit and brings on the indicator light.

I still don't know about the 4-wheel drive indicator light in the dash. I hope that when I replace the connector it will work, but some research indicates that I may need to replace the switch. JB conversions sells the new switch and connector and they think the old switch won't work. I'll let you know.

Of course, you have to re-align the front end.

I also installed a superlift tru-speed speedometer correction kit. I am running 35" wheels. My speedo was off about 20% with the old 3.07 rear. with the new 4.10 rear, I was only off about 5%. However, I am noticing that the engine is running much better than before.

All told, this project costs more than I planned. In retrospect, I probably should have just bought a rubicon and put in a lift kit. Nonetheless, I have it now.

Total costs

Axles, tcase $ 4300
labor $ 800
shafts $ 500
control arms $300
Tru-Speed $ 220
Wiring $ 150


So, all told, a bit over $6K. It definitely runs smoother with the new driveshafts and better power with the 4.10 gearing. I still haven't tried it in the woods. Coming soon.

Charlie

[472cid]

getting ready to do the same thing my self i am going to watch this thread and a link to the wiring would be awesome

[chino78415]

I just got the truspeed for my TJ. Any tips for the installation?

[Savvy]

The Truspeed unit is one of the easiet mods you'll do. You'll spend more time calibrating the unit while driving with a GPS than installing the unit itself. I like the unit as you have two switches that allow you to run different tire sizes.

[MQ79]

Here's a thread for with the part numbers you'll need to get the 4 wheel drive indicator light to work -

http://www.jeepforum.com/forum/f9/np241j-rock-trac-transfer-case-4wd-switch-revealed-651308/

It's how I did mine, and it works, the light comes on in 4hi and 4lo, and turns off in 2hi. But it stays on in Neutral, which isn't a big deal, but something to be aware of.

I had the exact same problem with my output seal too. I thought about having a custom piece machined, but didn't have the time. So I just sealed up the weep hole and RTV'ed the transfer case to the tranny. Probably not the best way, but it worked great and doesn't leak a drop.

I got lucky and my speedo is perfect, so I didn't have to adjust it at all. 4.56's and my tires measure 36.8".

[brokentoy]

How much does the truspeed unit cost? I see $220 in above post, but it appears to retail for about $250. Who's got the best price?

[Sol_Invictus]

So here's a stupid question. I have a 4 cylinder with the AX-5 behind it. I'm looking to purchase rubicon axles and transfer case to swap into my jeep. I can't afford to do an engine swap right now, and the rig is a semi-daily driver. Would I even be able to make this drivetrain work behind an AX-5? Is there another stick transmission I could bolt to the four cylinder that would work? I'm not interested in starting a debate about efficacy of the four cylinder, just wondering if this is possible. Thanks in advance.

[mcg311TJ]

Originally Posted by Sol_Invictus

So here's a stupid question. I have a 4 cylinder with the AX-5 behind it. I'm looking to purchase rubicon axles and transfer case to swap into my jeep. I can't afford to do an engine swap right now, and the rig is a semi-daily driver. Would I even be able to make this drivetrain work behind an AX-5? Is there another stick transmission I could bolt to the four cylinder that would work? I'm not interested in starting a debate about efficacy of the four cylinder, just wondering if this is possible. Thanks in advance.

It could work with the right adapters...Call AA and see if they got what your needing. if they don't, they can make it..

[472cid]

Originally Posted by Sol_Invictus

So here's a stupid question. I have a 4 cylinder with the AX-5 behind it. I'm looking to purchase rubicon axles and transfer case to swap into my jeep. I can't afford to do an engine swap right now, and the rig is a semi-daily driver. Would I even be able to make this drivetrain work behind an AX-5? Is there another stick transmission I could bolt to the four cylinder that would work? I'm not interested in starting a debate about efficacy of the four cylinder, just wondering if this is possible. Thanks in advance.

Yes you need the bellhousing from a dakota 2.5 which uses the ax15 trans and a jeep ax15. then when comes time to go with a six put jeep bell back on and put a 4.0 in. ax15 will bolt right to a 241j from a rubicon

[Sol_Invictus]

That's fantastic you guys rock. Are there specific years for the Dakotas? What clutch would I be running? Any other pertinent information? Thanks for the info.

[Sol_Invictus]

Anyone...?

[Sol_Invictus]

buehler...buehler....