Topic: AX-15 Swap?

[YJmechanic]

Anybody know what has to be done to swap from a 5 to a 15 in a yj?  From what I understand, there is no power differance but the durability is worth the swap.  I wouldn't imagine that it would be much change over cause they are very close and yj's don't have any tranny controllers or anything like that.  Any other good tranny ideas?

[StefanBidi]

You need the bellhousing out of a 2.5L 96-99 Dodge Dakota, and that's it.  The 4.0L uses a different bolt pattern, and the Dakota came with the AX-15 and 2.5L, so that's convenient.  You'll also want to get the AX-15 with the attached t-case.  The AX-5 bolts up to a 21-spline NP231, whereas the AX-15 bolts up to a 23-spine NP231.  There are kits available, but it's better to just get the matching t-case.

[YJmechanic]

Doesn't seem to bad.  But is it really worth the money rather than rebuilding the ax5?

[StefanBidi]

I think for you it will be!  You just did a "performace" rebuild on you engine, and even though the AX-5 isn't going to just explode, it'll wear a lot faster than it should.

[trailblazer95]

...and even though the AX-5 isn't going to just explode, it'll wear a lot faster than it should.

amen to that, i threw my clutch out three weeks after i put my supercharger on.

[Bounty Hunter]

Just a few things to watch for:

Not all AX15's are 23 spline, early 15's are 21spline.
Stick with a '94+ bellhousing to have an external clutch slave, and you'll likely need the clutch master cylinder if your present one is for an internal slave.
Make sure the AX15 is '94+, or be prepared to swap out the input cover in order to fit the throwout bearing.
Watch the overall length of the AX15, if it's much different than your AX5 it will affect the required driveshaft lengths.

[YJmechanic]

I think I may just switch to the 15 just for the durability and use a centerfoce dual friction clutch.  It all depends how bad mine is when I tear it down.  Syncros at my dealer cost are only like $80 so it that is my whole problem then I'll run it untill it really blows.

[Jeffy]

If you're going to bother going with an AX-15, I'd consider the NV3550, too.  It's the AX-15's replacement.  Better tranny overall and would be bulletproof on a 2.5L.  The NV3500's have been used in the Dodge Ram's with the 5.2L's.

[YJmechanic]

maybe it's better but how hard would it be to convert?  And if going that far wouldn't it be better to go to nv4500?  I also heard that 35-45 don't work well in yjcjtj because of the length

[StefanBidi]

The AX-15 and NV3500 are at least 100lbs lighter than an NV4500, and behind the 2.5L really will not make that much of a difference strength wise.  Not even a built 2.5L will make enough power to destroy one of those, unless you're running force induction.  Also, for the AX-15 there's already a junkyard bellhousing available and you won't have to spend an extra $500 is adapters, that you would with the NV4500.

The NV3500 also replaced the AX-15 in 2001 (I think), so it does fit comfortabily where the previous AX-15 used to.

[jwrape]

I just completed the swap. You need a 98' Dakota bellhousing for a 2.5L, a 84' Camaro clutch disc, 95 YJ throw out bearing, NV4550 pilot bearing, a 95' YJ slave cylinder(external) 23 splin input shaft installed in you xfer case. rear DS shortened 2" and a little bit of time.

Best conversion I ever did. I don't worry about my tranny falling apart on me any more. Cost me $800 for all parts including the $400 I paid for the used AX15.
You can read all about it here
http://www.pirate4x4.com/forum/showthread.php?t=181361&page=6&pp=25&highlight=ax-5+swap

[Jeffy]

Have a complete parts list by any chance?  I've got some of that POR thread posted in the FAQ, I think.  Or even better would be a write-up.

I've thought about swapping but haven't really had the need.  Although I'm going to have to make a choice once I get into stage 2 of my project which involves the rest of the drivetrain.

[jwrape]

Have a complete parts list by any chance?  I've got some of that POR thread posted in the FAQ, I think.  Or even better would be a write-up.

I've thought about swapping but haven't really had the need.  Although I'm going to have to make a choice once I get into stage 2 of my project which involves the rest of the drivetrain.

I don't have a parts list but I got most of them through Advance adapters and Autozone. The clutch disc was a little hard to track down but the cheapest place was AZ. The slave cylinder extention line, 23 spline input shaft, pilot bearing came from AA, the bell housing I found at a junk yard, the slave cylinder, throw out bearing were from AZ. All these parts ended up being about $400.

That thread above has all the part numbers you need in it. Also Advance Adapaters is VERY knowledgeable about these different parts and very willing to help.


The other thing I would suggest is getting an inertia ring from Tri-county 4x4. While you are there you might as well add it to your flywheel. You will definately thank me for it.
http://www.4x4wire.com/tech/clutch/inertiaring/

[Bounty Hunter]

Let us know what you think of the inertia ring after you run it a while.

[Jeffy]

Let us know what you think of the inertia ring after you run it a while.

Who me?  I haven't even decided if I want to stick with the AX-5 or not.  I haven't had any problems with mine other then notchy shifting.