4x4 Conversion Bummer

[ChillyB]

Bought some donor parts for a 4x4 conversion to my 1995 XJ, including an AW4 mated to a 231. However, I just noticed the sticker on transfer case says 1999, and the AW4 has an input speed sensor, confirming the duo is from a too-late-to-be-simple Jeep. My limited understanding is the OUTPUT speed sensor is different with pulse rate 4x what my TCU should be receiving (I learned that here, THANKS).

I DID also read a post suggesting one could swap over the Olde Tyme reed valve type OSS do-dads and make that transmission work. There were red X's where photos had once been so I don't yet have any idea what this would entail.

Also, I will be taking off a 2WD AW4, which one might hope will contain all the parts to do this OSS conversion. What do you all think?

Alternately, I might be able to roll down to Dex's XJ to horse trade into the correct tranny and transfer case. He's 2.5 hr from me.

What would the smart kids do in this situation? Is there another difference In not anticipating?

Thanks!
Chilly

 

[Unclewolverine]

I don't know if the 2wd sensor wheel is the same or not but you for sure the pre 97 transfer case adapter.

 

[ChillyB]

I don't know if the 2wd sensor wheel is the same or not but you for sure the pre 97 transfer case adapter.

For sure the pre-97 transfer case adapter... is the same? Not the same? You faded out.

 

[ChillyB]

Wait a dadgum....

Am I way overthinking this? Why did I think a 2WD AW4 was a solid housing clear back to tail shaft? Can I mix and match innards and outards to make something out of what I have?
- keep the 95 tranny, remove the tail shaft housing.

- swap the 99 tranny output shaft into the 95 2wd tranny.

- retain the 95 output speed sensor.

- do something to splice the 99 transfer case VSS onto the harness that had been going to the 95 2WD VAS (is that possible?).

 

[ChillyB]

the more I read...

Here's what I think might be possible.
1. Remove 2wd tail piece from my 1995 XJ native transmission.
2. Remove 231 from the 1999 AW4, measure output shaft length.
3. Cut the transmission output shaft to match length of the 4wd 1999 AW4
4. Move the transfer case from 1999 onto the 1995 AW4.
5. Plug VSS into the transfer case.

Could it be that simple? This leaves me a spare 1999 AW4 for my other XJ, which is a 2000, or sell it.

 

[Unclewolverine]

I'm pretty sure you can't adapt a 2wd to make it work with the case. To make this work you need the pre 97 adapter between the 4wd tranny and the case because the sensor is clocked differently and depth is different, you also need the matching counter wheel for the sensor.

 

[RCP Phx]

Kastein has covered about everything on compatibility in his thread!
https://naxja.org/threads/everything-you-ever-wanted-to-know-about-the-aw4.1053970/

 

[ChillyB]

Kastein has covered about everything on compatibility in his thread!
https://naxja.org/threads/everything-you-ever-wanted-to-know-about-the-aw4.1053970/

Read it a few times. This is where I'm at:

• 1998-2001 AW4s require more work. All the transfer case input gear info from 1990.5-1997 applies, on top of that, the sensors have changed! You can either build the circuit given here by lawsoncl or swap the transmission tailhousing, sensor drive rotor, and output speed sensor as shown here by Frank Z to make this work. You may need to add custom wiring for the transfer case indicator lamps (see above.)

I'm interested to know what Frank Z did but his post shows only red X for photos and since I've not been inside these yet I can't imagine what he did to covert/modify. Seems like a fellow could grind off three of the four lobes of a reluctor ring to quarter it's pulse rate. Maybe splice on a different rear output sensor connector? The post seems like exactly what I need but not enough detail for an auto tranny new guy, I guess.

 

[ChillyB]

I think it appears I'm all over the map. In a way I am. I am considering two options: mod my existing 1995 XJ 2WD AW4 to take a 231, or mod my 1999 spare 4WD tranny to work in my 1995 XJ.

Between cash for clunkers and the EPA (and that the newest XJ is 23 yr old) all of the salvage yards around here are gone. Otherwise I'd horse trade my 99 assembly for the appropriate year.

 

[ChillyB]

Are the 4WD tranmission tail housing adapters the same throughout the years, or is there a difference that coincides with the change in output speed sensor configurations?

 

[RCP Phx]

Are the 4WD tranmission tail housing adapters the same throughout the years, or is there a difference that coincides with the change in output speed sensor configurations?

No on the first and yes on the second.

 

[ChillyB]

No on the first and yes on the second.

So eBay sellers advertising them as 87-01 don't know what they have. I can see this is going to be a hoot.

 

[Ghost]

I think it appears I'm all over the map. In a way I am. I am considering two options: mod my existing 1995 XJ 2WD AW4 to take a 231, or mod my 1999 spare 4WD tranny to work in my 1995 XJ.

Between cash for clunkers and the EPA (and that the newest XJ is 23 yr old) all of the salvage yards around here are gone. Otherwise I'd horse trade my 99 assembly for the appropriate year.

To mod the 95 you would have to change the output shaft which requires you to tear the transmission all the way down. OS come out the front. I didn't see that mentioned. My experience is with 94's.

 

[ChillyB]

To mod the 95 you would have to change the output shaft which requires you to tear the transmission all the way down. OS come out the front. I didn't see that mentioned. My experience is with 94's.

Seems common for people to shorten rear output of t-case for a SYE install. Why wouldn't I just cut the tranny output shaft to required length with it still installed? I realise it's hardened so requires more than a hacksaw.

 

[Ghost]

Seems common for people to shorten rear output of t-case for a SYE install. Why wouldn't I just cut the tranny output shaft to required length with it still installed? I realise it's hardened so requires more than a hacksaw.

Best guess is the splines don't go far enough in. But that is uncharted territory for me. You might could check that by measuring the tow past the rear of the case maybe?

 

[Unclewolverine]

Seems common for people to shorten rear output of t-case for a SYE install. Why wouldn't I just cut the tranny output shaft to required length with it still installed? I realise it's hardened so requires more than a hacksaw.

As often as people change 2wd xjs to 4wd it seems if that was possible it would of already been done, and a write up created. If it was as simple as hacking off the tail shaft and bolting on a transfer case all of them would be 4wd by now.

 

[RCP Phx]

You can't cut the shaft (no splines there) you have to replace the shaft or get a compatible trans!