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Everything you ever wanted to know about the AX15 (and some about the AX5)

There is also the outer diameter to consider, depending on the crank being used.

The 4.2L crank was different from the 4.0L crank. This comes into play when doing a stroker on a 4.0L motor, which uses the 4.2L crank. I messed with all this when I did my stroker. Now, where are my notes.....

From Phoenix Friction Products
https://www.phoenixfriction.com/
877.570.5630

4.2L Engine
ID: 0.580”
OD: 1.056”
P/N PB122

1995 Cherokee 4.0L Engine
ID: 0.755”
OD: 1.001”
P/N PB207

Used for me:
ID: 0.755”
OD: 1.055”
P/N PB 117

4.2 L Crank used a bushing (or bearing) that is 1.056” diameter
4.0 L Crank uses bushing that is 1.001” in diameter
Early AX-15 transmissions have a input shaft that is 0.580” in diameter
Later (1992?) AX-15 transmissions have an input shaft that is 0.755” in diameter

So, stroker in a later model AX-15 would use PB 117. Stroker in an earlier model AX-15 would use PB 122.


Hopefully, this helps, and doesn't just make it more confusing.




David Bricker / SYR
 
Annnd, I'm guessing Ken has already covered this previously in this thread, so this is probably old news.

David Bricker / SYR
 
Thanks guys!! I ordered a new bearing retainer cover and determined that there was no difference. I’ll be glad to finally get this issue of having a problematic internal slave cylinder set up resolved, as I’ve beckne entirely too proficient st pulling the transmission on my YJ.

It is Interesting how a lot of these issues weren’t resolved congruent to corresponding year models. I suppose this was due to the financial issues of AMC at the time of the CJ/YJ conversion. They were indeed practicing field engineering with a lot of the enhancements that were attempted on the YJ platform which was intended to make the jeep a commercial staple as opposed to a reworked military platform.

No one ever buys an old jeep with that notion of not having to work on it!!
 
Re: Parts Need Going from AX5 >> to >> AX15 ??

I have a 1997 AX5 equipped 4.0 XJ with NP231 xfer case. The AX5 has developed the problem of not staying in 1st gear.

The transmission shop won't rebuild it, and wants $1500 to swap out with low-miles used AX5.

I'd prefer to replace the AX5 with an AX15 on my own.

From what I can tell in this thread, I would need:
  1. Used AX15
  2. AX15 compatible bellhousing
  3. Appropriately-sized pilot bearing
  4. New clutch, pressure plate and throwout bearing
Used AX15

Does anyone know if there are any other other unique-to-AX15 parts I would need?

This may be a long shot. I have had several manual transmissions that would jump out of gear. Last month my Tacoma was doing this. I pulled the gear shifter and the little bushing that the shifter sits on was all crumbled up. I replaced that and problem solved. Hope this helps
 
There is also the outer diameter to consider, depending on the crank being used.

The 4.2L crank was different from the 4.0L crank. This comes into play when doing a stroker on a 4.0L motor, which uses the 4.2L crank. I messed with all this when I did my stroker. Now, where are my notes.....

From Phoenix Friction Products
https://www.phoenixfriction.com/
877.570.5630

4.2L Engine
ID: 0.580”
OD: 1.056”
P/N PB122

1995 Cherokee 4.0L Engine
ID: 0.755”
OD: 1.001”
P/N PB207

Used for me:
ID: 0.755”
OD: 1.055”
P/N PB 117

4.2 L Crank used a bushing (or bearing) that is 1.056” diameter
4.0 L Crank uses bushing that is 1.001” in diameter
Early AX-15 transmissions have a input shaft that is 0.580” in diameter
Later (1992?) AX-15 transmissions have an input shaft that is 0.755” in diameter

So, stroker in a later model AX-15 would use PB 117. Stroker in an earlier model AX-15 would use PB 122.


Hopefully, this helps, and doesn't just make it more confusing.




David Bricker / SYR
I covered some of this but not all.

For what it's worth, at least on HO stuff, I've never ever had to worry about the 1 vs 1.055 pilot bore, because the fc69907 pilot bearing for a 92-up 0.75 pilot tip fits into the larger 1.816" pilot bore that is designed for the AW4 converter snout. 90XJay also used this route for his 90 RENIX he put a late model AX15 into, but no idea what year the crank was.

I don't know if 258 cranks have the right shape either... But it occurs to me that there's one sitting in my closet so I'll check it in a moment.

I don't know of a pilot bearing with a 1.816 OD and small pilot tip (0.59 I think?) Though.

Edit: can't find my caliper anywhere, but using a tape measure for a "looks good from my house" precision machining measurement, I come up with 1-13/16” which is pretty close to 1.816. so I'm pretty sure that would fit an fc69907 to take a 92+ AX15 as well. No idea on 0.59" x 1.816" pilot bearings, you're on your own for that...
 
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So, slighty OT, maybe, doing a 4wd swap in my MJ. MJ is renix, and has pos BA10/5.
Will be external slave, does 94-96? Or later slave master matter? Is it just pedal based or?
Thanks.
 
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