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JT Gibbs 01-17-2010 10:17 PM

Engine Swaps
I own a '97 Wrangler with a 4 inch lift and 32's and I want more power, I have a lil 4 banger manual 5. I want to swap in an I6, but I heard the AX-5 transmission which should come with the I4 is really weak and to use an AX-15 transmission with the I6. Question is, will the AX-15 replace the AX-5 without having to modify my floor for the new shifter.

Also my check engine light came on the other day, so I tried the on/off deal that everyone says to use, and it doesn't work.

Twozerofd 01-17-2010 10:43 PM

I have my old I6 motor if you are interested. It has 75k on it, out of my 2004 Rubicon. Let me know if you are interested.

JT Gibbs 01-17-2010 10:45 PM

That doesn't really answer my question, but good to know. There'd just be a shipping issue, and cost.

4Jeepn 01-17-2010 11:11 PM

To answer you question.. the shifter should be in about the same place. Also and you may not want to hear this, it may prove cheaper to sell your current jeep and buy a 6cly.

JT Gibbs 01-17-2010 11:19 PM

I have put way too much time and money into this thing plus it's my first car to sell it. I will post some before and after pix soon. I bought it totaled, my father owns an auto body shop.

schnutzy 01-17-2010 11:29 PM

isnt the spline count on the output shaft of the AX-5 different then the one on the AX-15?

JT Gibbs 01-17-2010 11:36 PM

I don't know, I just know the AX-5 is supposed to be really weak.

JT Gibbs 01-17-2010 11:40 PM

1 Attachment(s)
Here's my Jeep currently

schnutzy 01-17-2010 11:43 PM

yeah, AX-5 has a spline count of 21, where the AX-15 is 23. so if you do a tranny swap, u might have to pull the t case out of a 6 cylinder jeep.

for more info: The Novak Conversions Transmission Information Gateway

schnutzy 01-17-2010 11:44 PM

real nice jeep btw. i love that blue

JT Gibbs 01-17-2010 11:47 PM

Ok, transfer case isn't a big deal. I was mainly wondering about the shifter position. Also about the other problem, my check engine light came on, so I did the on/off with the ignition but nothing happened.

distortedtj 01-18-2010 01:28 AM


Originally Posted by JT Gibbs (Post 525465)
Question is, will the AX-15 replace the AX-5 without having to modify my floor for the new shifter.

No mods to the floor needed. The AX-5 is not a bolt on behind the 4.0L AND the AX-15 will not bolt behind the 4banger.

Also my check engine light came on the other day, so I tried the on/off deal that everyone says to use, and it doesn't work.

The ol' turn the key back and forth does NOT work on all jeeps. Yours being a earlier 97 I doubt it does.

Good looking jeep bud. And if I recall I seen the build for it on another forum.

With you wanting to change to a 4.0L you will need everything. Engine, trans, t-case, computer and wiring. Best bet is to find a wrecked TJ or pull it all from an XJ.

Bouncy 01-18-2010 06:00 AM

Shifter should fit. Jeep/Chrysler wouldn't design two different bodies.

Engine, trans, t-case swap is a big deal. But even bigger is rewiring the entire jeep.

You will need engine harnesses, new ECU, new power/ground lines etc. So consider that when your thinking of a swap.

Not sure why the 21/23 spline tranny came up. I thought that problem ended back in 1990/91 with the XJs. Then again I am new to the TJs so most of my info comes from XJ swap info.

JT Gibbs 01-18-2010 06:35 PM

I read in the 4x4 Garage TJ edition magizine, and they said mopar sells a wiring harness that splices into the existing harness if you do the swap I am wanting to do. But I'd need all of that, computer, harness, ect.?

Bouncy 01-18-2010 06:48 PM

Not sure about your splice harness.

The swaps I have seen included removal of all wiring from the computer to the engine and replaced with 4.0L harness and computer. Its kinda a big swap but if your a patient person, it can be done.

Donor jeep is needed for engine, accessories, harness, computer. A good manual/FSM and some good eyes for the electrical pages helps.

JT Gibbs 01-18-2010 07:12 PM

Would it just be easier to find a donor jeep and then just move the tub/fenders and everything to it? I am not a patient person at all, lol. I wasn't really expecting to have to do that much for a swap.

Bouncy 01-18-2010 08:31 PM

Its hard to say which is easier.

Me personally...I would have started with a 4.0. I kinda picked my TJ and still didn't get everything I wanted. I passed up about 5 others cause I wanted a 4.0 auto in good shape. Everything else was just parts I needed to find like a hard top and D44 rear.

JT Gibbs 01-18-2010 08:43 PM

I was needing a car, and this one sorta fell in my lap, paid 700 cash for it, now I have over 5,000 invested in it and a lot of time. So, engine swap is my only choice.

Bouncy 01-18-2010 09:01 PM

My HONEST opinion. It would be easier in the long run for more power alone to swap in an old 350 motor, trans and mait it to your t-case.

You would still have some wiring to do. But it is probably easier to do a carbed 350 than mess with all the wiring to do a 4.0 swap. Others that may have done the 4.0 swap may have a different opinion.

JT Gibbs 01-18-2010 09:07 PM

What about the transmission?

distortedtj 01-18-2010 10:58 PM


Originally Posted by JT Gibbs (Post 526122)
What about the transmission?

If your asking about your AX-5 behind a 350???

No. It won't bolt up and it wouldn't last 5 minutes behind a 350 if you made adapters to get it to bolt up.

There are adapter for a AX-15 to bolt up behind a 350 but still wont last long.

If you were to do a 350 swap you'll want the engine and trans.

4.0 swap isn't hard just need a donor. XJ's are easy to come by and for cheap. You would be hard pressed to find a full TJ donor vehicle.

And with ANY engine swap you will need to redo the wiring and computers/ for fuel injection. For carb you will have to do new wiring.

JT Gibbs 01-18-2010 11:02 PM

What I ment was, the tranny that mates with the 350, would I have to mod the floor for the shifter?

distortedtj 01-18-2010 11:03 PM

Yes. Not much just cutting a little sheet metal away. With auto or manual trans. Haven't done one or seen one yet that wasn't trimmed back some.

JT Gibbs 01-18-2010 11:08 PM

I just need more torque, basically. Would it be worth the money to install aftermarket intake and exhaust, and possibly a throttle body spacer. Change out the spark plug wires and spark plugs? This thing has 154XXX miles on it so I suppose it's going to go soon. I have put 1,000 miles on it since I bought it back in aug. of '08.

distortedtj 01-18-2010 11:17 PM

Nope.. to all that stuff on a jeep to give you torque. A 4.0L TB is the only "add on" I would suggest for power out of you 4 banger.

Torque= gear swap.

If you want the torque back from the larger tires you need to change the gears. No matter what you "bolt on" it isn't going to fix the rolling mass of your tires except for gears.

JT Gibbs 01-18-2010 11:20 PM

Fun, guess I'll save up for a swap. So, I should have a enough money this time next year.:(

distortedtj 01-18-2010 11:23 PM

Depends. With the 350 fuel injected its not cheap.

Could buy a wrecked 4.0L XJ for $500 to $1000 and have pretty much all you need.

Gear change to adjust to your tire size $1000 to $2000 depending on your area.

IndyJeepMan 01-18-2010 11:23 PM

Or you could get smaller tires... 4cyl's have plenty of power (low end) for any occasion really. Trust me I have one too..

I used to have an I6, that is.. In my old Jaguar XJ6 haha.

JT Gibbs 01-18-2010 11:31 PM

I think the tires fit perfectly under my jeep. I have 32's on it now, I originally had 33's on it.

IndyJeepMan 01-18-2010 11:34 PM

I have 31's you shouldnt be seeing a lack of power on the low end. When I take off the frame slightly flexes to the right on mine.. Yes the high end is crappy but its a jeep..

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