Swapping an AW4 into a 91 XJ w/ a busted AX5

ATTN: Old_Man(Tom)Swapping an AW4 into a 91 XJ w/ a busted AX5

Howdy,

I have a bit of a situation, and heard that .org was the place to come for the experts on XJ customization.

I've got a 91 XJ(I4, mainly stock) that I am dieing to get back on the road; wife busted up the stock AX5 tranny.

While I think I'll open up the AX5 and see about putting in whatever gears are chewed up, maybe doing a master rebuild kit as well, I have another option that I wanted to run by you fine folks:

I have a '88 XJ(6 cycl with AW4 tranny) that I picked up for a song a while back(engine needs to be overhauled/rebuilt). It's just sitting here atm, and it's got a rather good conditioned AW4 tranny that I'm thinking I could slap into the 91 with the busted AX5. Here's what I think I know so far:

The '88 XJ's AW4 has a TCM that's seperate from the ECM, that means that if I can find the schematics, I can solder in the TCM to the 91's ECM fairly easily, right?

The AW4 is a bit longer than the AX5 tranny, the rear driveshaft will probably give me trouble, right? I do have the driveshafts for the 88, if that will help me out any. Will it? I don't see how, but something told me to ask anyway...

Most people who do this swap notice that the AW4 tries to change gears from 1st to 2nd while in low gear selection mode, that's not something I have to worry about right away as I rarely use LG, but any info on it is appreciated.

Here's some things I can't even act like I know:

The AW4 should bolt up to the I4 engine pretty easily? I haven't dropped the AW4 out of the 88, as I'm still trying to plan this out.

I know this will be a task, but is it going to be so bad that I should just think of rebuilding or replacing the AX5? I'd like to save the money, and have the time to make the swap, but some of you guys who may have experience here will know what is most feasible.

Sorry for the long first post, but I tried to get as much info out to ya'll as I could.

Flip.

Edit- Thanks for the tip Dirtclod, I changed the title, hope he reads it.

Talk to Old_man (Tom). He did this about a year ago. I think his biggest headache was the wiring harness.

Hi there,

I tried to edit the title but it seems that didn't work. Anyway, thanks for the tip, I shot him a PM with the post's contents.

Anyone else have any experience with this?

Flip

Tom replaced the 4 with a 6 cylinder, and put an AW4 in at that time. The 4 and 6 have different bellhousing patterns. The AW4 will not bolt up to it.

The I4 an I6 have totoally different bell housing bolt patterns and are not interchangable, even if they where the output spline counts are different 23 for the ax and 21 for the aw4.

the I4 came with a tf904 in early years and the tf 999 in later years both are 3 speeds without OD. Supposably there is the all elusive aw4 for the I4 that has yet to be found but is supposed to exist.

If you could find it the bellhousing culd be used to fit onto your aw4...only if LOL

If your 88 is a parts rig, you will need everything off of it that controls or interfaces with the AW4. I swapped a 96 AW4 into my 89 XJ a few years back.

Here's a short list of what you'll need to help you decide if you want to pursue this:

AW4 tranny
TCU and wiring harness (must be grafted into your 91 harness)
Flexplate
Auto Brake pedal (optional)
Auto brake switch ( also controls TC unlock)
Auto Shifter, linkage, console bezel
Auto TPS
Kickdown cables
Aftermarket Tranny cooler (highly recommended)
T-case input shaft (some are 21, others are 23 spline, need to match with AW4 output)
Move crossmember back to rear mounting holes
Modify rear driveshaft/use auto ds

Plus several small items that are currently slipping my mind.
Hope this helps. I'm glad I did the swap on my rig and I never miss the BA/10-5.

XJEEPER said:

If your 88 is a parts rig, you will need everything off of it that controls or interfaces with the AW4. I swapped a 96 AW4 into my 89 XJ a few years back.

Here's a short list of what you'll need to help you decide if you want to pursue this:

AW4 tranny
TCU and wiring harness (must be grafted into your 91 harness)
Flexplate
Auto Brake pedal (optional)
Auto brake switch ( also controls TC unlock)
Auto Shifter, linkage, console bezel
Auto TPS
Kickdown cables
Aftermarket Tranny cooler (highly recommended)
T-case input shaft (some are 21, others are 23 spline, need to match with AW4 output)
Move crossmember back to rear mounting holes
Modify rear driveshaft/use auto ds

Plus several small items that are currently slipping my mind.
Hope this helps. I'm glad I did the swap on my rig and I never miss the BA/10-5.

Click to expand...

HE has an I4 engine which means he would also have to install the 4.0 and stuff to go with it

Hmm, sounding like a quick rebuild will serve my purposes better.

Can't I find a bellhousing adapter from somewhere like advance adapters? Probably not the most desired combo and I don't think I want to pay for a one off fab, yeah probably not. The output spline would be another pain...

Ok that's a good case against it, I'll look further into my rebuild/replace options. Thanks for the great replies, I really appreciate it.

Flip

On a side note, the 88's not really a parts car, it's complete with the engine in pieces at the moment but other than that it's got all it's gear. I don't even know why I bought it other than it was so cheap and I love jeeps, a curse or a passion I guess. Maybe I'll look into parting her out or selling her off *shrug*.

xjnation said:

HE has an I4 engine which means he would also have to install the 4.0 and stuff to go with it

Click to expand...

Missed that part......if I were wearing your shoes, I'd spend my time and money on the 88, find a late model junkyard 4.0 to replace the tired one.