Everything you ever wanted to know about the AW4

[pencilrunner]

This thread is gold - just read every post in a sitting. THANK YOU ALL!


Need to verify my approach with y'all on something.


I have a '97 XJ 2WD w/ solid body - and a '00 XJ 4WD with a destroyed body.


I'd like to swap the 4WD AW4 etc. to the 2WD body. My approach in regards to the AW4, as I understand it:


'00 AW4 and TCase, TCU, and associated wiring from between these items come from the '00 and go into the '97. It may be a pain to do the loom work, but that's the cleanest approach, yes? Another option would be to go splice-crazy and keep the '97 TCU?


Wondering what the best approach would be (short of finding a donor '97, that is). Money is tighter than labor hours, as this is not a daily driver.

[RCP Phx]

Originally Posted by pencilrunner

This thread is gold - just read every post in a sitting. THANK YOU ALL!


Need to verify my approach with y'all on something.


I have a '97 XJ 2WD w/ solid body - and a '00 XJ 4WD with a destroyed body.


I'd like to swap the 4WD AW4 etc. to the 2WD body. My approach in regards to the AW4, as I understand it:


'00 AW4 and TCase, TCU, and associated wiring from between these items come from the '00 and go into the '97. It may be a pain to do the loom work, but that's the cleanest approach, yes? Another option would be to go splice-crazy and keep the '97 TCU?


Wondering what the best approach would be (short of finding a donor '97, that is). Money is tighter than labor hours, as this is not a daily driver.

Did you thoroughly read post#1?

[Tim_MN]

The simplest and cheapest approach is to sell what you have, and buy what need.

[lawsoncl]

Originally Posted by pencilrunner

This thread is gold - just read every post in a sitting. THANK YOU ALL!


Need to verify my approach with y'all on something.


I have a '97 XJ 2WD w/ solid body - and a '00 XJ 4WD with a destroyed body.


I'd like to swap the 4WD AW4 etc. to the 2WD body. My approach in regards to the AW4, as I understand it:


'00 AW4 and TCase, TCU, and associated wiring from between these items come from the '00 and go into the '97. It may be a pain to do the loom work, but that's the cleanest approach, yes? Another option would be to go splice-crazy and keep the '97 TCU?


Wondering what the best approach would be (short of finding a donor '97, that is). Money is tighter than labor hours, as this is not a daily driver.

The 1997 TCU isn't going to work with the 2000 transmission, because the output sensor pulses 4 time/rev, and the 97 TCU is expecting 1 pulse/rev. You'll be in 4th gear by the time you hit 30 mph. There are conflicting reports whether a 97 TCU works in the 98+ without triggering a check engine light, but I haven't seen anyone trying the opposite yet. I'm guessing here, but I would try transplanting the 2000 TCU and see if the 97 engine computer is happy with it. If you try this, please report back whether it worked so we can update the first page of this thread.

[kastein]

Agreed. I still have no solid info on 97 TCU+trans in 98+, nor 98+TCU+trans in 97.

[pencilrunner]

Originally Posted by lawsoncl

There are conflicting reports whether a 97 TCU works in the 98+ without triggering a check engine light, but I haven't seen anyone trying the opposite yet. I'm guessing here, but I would try transplanting the 2000 TCU and see if the 97 engine computer is happy with it. If you try this, please report back whether it worked so we can update the first page of this thread.

Thank you, all - I know that the preferred option would be to do a tailcone/sensor swap from a '97 (or earlier?) AW4. Good lord I wish I could, but the pickings are slim, here. It's a budget build for sure, especially since the budget is that of a 17yo high schooler, so that adds a level of difficulty



I can certainly try the '00 TCU and hope it doesn't throw a CEL, but I may do (but certainly will prepare for) a slightly different approach.



I was thinking of pulling the entire transmission-related harness wiring from the body of the '00, and working that into the '97. I know that is borderline insane, with the level of effort required, but short of hunting down a tailpiece/sensor that'll work, it may be the only way.


God smiles on drunks and idiots, so here's hoping!

[Pirate_71]

Ok folks this is my first post or reply to the site. I am thankful for the information. I will share some information that may be beneficial. You can think whatever you want about what I’ve done, but it was purely out of necessity.
I have successfully installed an 95 transmission in a 98 XJ. Following is as detailed a list of modifications as I can give.
First of all this XJ is a trail rig and is only driven to local trails or trailered to trails that are further.
The trans case had the casting for the ISS but it was not machines out.
I removed the pump and the overdrive hub, packed paper towels into every orifice and any crevice where filings could migrate into.
Pay close attention to how things come apart, take pictures and if possible have an exploded view diagram.
Measuring the outside diameter of the Sensor with a micrometer, I determined that a 19/32 drill bit would get me closest, but finding one in a rural community posed a challenge, so a 37/64 drill bit acquired from the local fastenal was the best I could do in short order and it actually worked out much better. The hole for the mounting bolt was pre-drilled and tapped, but would not have been a big issue if it wasn’t.
With the hole drilled, I test fitted the sensor several times and used the drill bit to take small amounts of material out of the hole for a good fit. This is delicate work with a heavy tool so take your time.
The transfer case adapter is different, so you have to swap those out for the newer style OSS.
Also the newer style counts 4 pulses per revolution the old style only counts 2, so the piece that slips into the output shaft has to be changed. This presented a different issue as the new one is wider than the old one, so I slipped it onto the output shaft and , marked the shaft to show where the snap ring needed to sit.
Again using paper towels to seal off any opening, I used a 4-1/2 angle grinder with a thin cutoff wheel and created the recess for the snap ring.
Installed the 4 pronged counter with the key and installed the snap ring, used carburetor cleaner and compressed air to clean the shaft and housing, re-installed the transfer case adapter, installed the wiring harness from the 98 transmission, installed a new filter, gasket and installed the transmission into the 98 XJ, filled it with fluid and test drive it. The Transmission works flawlessly.
Now before anyone starts hating on the way this was done let me say, if you have never been in a position that you had to have something done and ready to roll by morning, you will never need this type of information. I am a heavy industrial mechanic by trade and I understand the dangers of scoouring a hardened shaft. As for drilling the bing for the ISS, thaw sensor does not leak and I would challenge anyone to show me the detriment of doing this modification.
So in short, can it be done? YES
Should it be done? I would say that depends upon your circumstances.
I greatly appreciate the information provided on this thread and I hope this has been a help to someone else.

[kastein]

The old style OSS rotor actually only counts one per revolution - if you look at the back of the rotor you'll see only one lobe has a magnet, the other is there for balancing. Good catch on the difference in thickness and different snapring slot, I had forgotten that detail.

I would certainly agree with your assessment of whether it can/should be done - it's not something I recommend to most people, but if you are up against the wall and on a strict timeline, you play the hand you're dealt, not the one you wish you had. Well done, that's not a set of modifications I'd wish on anyone working under those conditions!

[chris420]

Why not swap everything from the 2000 over to the 1997? It should all bolt in just take a lot of pictures and or videos when disassembling. While your at it you use dielectric on everything.

[chris420]

You can also replace things like heater core and ac condenser.

[GreenMachine1]

Hi everyone! This is an extremely informative thread. Thanks to all who contributed.

I recently picked up a very clean (for the Northeast) 2000 XJ Limited 2wd. The plan is to convert to 4wd so I set out to convert the 2wd AW4 to 4wd using a 97 4wd AW4 donor I had kicking around. I have access to a transmission shop so I decided to do a complete overhaul since the transmissions needed to be completed disassembled to assess the snap right securing the output shafts into the transmission housings. I found on the hard way that the 97 AW4 didn't make a great donor as it uses a different output speed sensor, thus, mounting hole in extension housing is different, snap ring groove on output shaft used to secure the speed sensor pick-up is in a different location, etc. I took some pictures of these differences and can share if anyone would like.

Anyway, I picked up a reman torque converter from Transtar and installed it into the transmission tonight. I measured the distance between the bell housing and one of the mounts on the converter and got ~0.825", where as the spec in the 1997 FSM says 0.650". Is there a difference in the factory spec between '97 and '00? I don't have a '00 FSM.

Should I be concerned about this? I know the TC will pull out slightly when installed on to the flex plate but I don't want to shear the drive lugs off the inner pump gear if it pulls out too far. I have the original factory TC that came out of the '00. I plan to measure the overall height of it and compare to the height of the reman TC to make sure the reman unit wasn't welded incorrectly.

Please let me know if you have any insight.

Thanks,
Noah

[RCP Phx]

Originally Posted by GreenMachine1

Hi everyone! This is an extremely informative thread. Thanks to all who contributed.

I recently picked up a very clean (for the Northeast) 2000 XJ Limited 2wd. The plan is to convert to 4wd so I set out to convert the 2wd AW4 to 4wd using a 97 4wd AW4 donor I had kicking around. I have access to a transmission shop so I decided to do a complete overhaul since the transmissions needed to be completed disassembled to assess the snap right securing the output shafts into the transmission housings. I found on the hard way that the 97 AW4 didn't make a great donor as it uses a different output speed sensor, thus, mounting hole in extension housing is different, snap ring groove on output shaft used to secure the speed sensor pick-up is in a different location, etc. I took some pictures of these differences and can share if anyone would like.

Anyway, I picked up a reman torque converter from Transtar and installed it into the transmission tonight. I measured the distance between the bell housing and one of the mounts on the converter and got ~0.825", where as the spec in the 1997 FSM says 0.650". Is there a difference in the factory spec between '97 and '00? I don't have a '00 FSM.

Should I be concerned about this? I know the TC will pull out slightly when installed on to the flex plate but I don't want to shear the drive lugs off the inner pump gear if it pulls out too far. I have the original factory TC that came out of the '00. I plan to measure the overall height of it and compare to the height of the reman TC to make sure the reman unit wasn't welded incorrectly.

Please let me know if you have any insight.

Thanks,
Noah

I'll be curious as to what you find out. The torque converter and rebuild kit will be here tomorrow for my 2000 but I haven't made plans for my teardown yet.

[GreenMachine1]

Although I don't think this matters, I did use the pump body with gears and stator support shaft from the 97 donor trans as it was in better shape than the 2000 unit. To my knowledge, the pumps were the same for the A340 and AW4 from 1985 and up.

The ATSG manual says the spec should be 0.689" on 4cyl and 0.650" on 6cyl but doesn't specify years. The 1997 FSM agrees with ATSG. AllData says 0.112" for 2000XJ with AW4, but I must say AllData has been wrong in the past.

I look forward to hearing from someone who may have knowledge about this

[GreenMachine1]

I took a look at the wear marks on the original pump inner gear from the 2000 xj and it looks like the drive lugs weren't fully engaged during operation. In one picture you can see the pump sitting flush on the TC with full lug engagement and in the other picture you can see the pump sitting proud ~0.180". I think this should be okay but I'm surprised the FSM spec is so far out from what I am measuring. I wish I measured the gear thickness of the 97 pump. Based on tolerance stack, the pump body with gears is located off the transmission housing and the converter hub bottoms out against the stator support. The measurement in the FSM references the bell housing to mounting pad on TC. Are the bell housings different between 1997 and 2000? I'm fairly certain I am using the original 2000 bell housing.

FYI, the factory TC measured 0.018" taller than the reman, which doesn't explain the ~0.180" discrepancy between my measurement and the FSM.

Thoughts?

Sent from my SM-N950U using Tapatalk

[swedepowr1]

I've got a '97 XJ, and cannot find a '97 in our area. I have shifting problem into 3rd gear, freewheels in 3rd, until shifts back to 2nd. Disconnected TCU, trans will not shift out of 1st gear. trans bad, right? got a '98 trans. swapped tail-housings between '97 and '98. ok to bypass ISS from '98 trans to run in '97? to swap harness out of '97 trans, its extremely brittle. anyone make aftermarket harness or advice please! Non-NSS connector different on '97 and '98.

tried:4882174, 83503722, 56009463, 56009385

Thx for any advice!