99 xj transmission swapped into 97 electrical issue

[Jcovatto]

Good evening,
I have a 97 xj that the trans went out. The guy I got the new one off of had a 99 and said it would work. So we bought it and installed it. Found out the wire harness is different ( 5 prong to a 7 prong). I called the guy and he said just rewire it to match the existing harness in the 97. Got it all done and when we put it into drive it only wants to stay in 3rd. Manually I can get it to start in 1st to 2nd but at the switch to 3rd they want run simultaneously. What I have looked at do I need to switch my TCM to a 99 and run a new harness to get this fixed? Has anyone else ran into this issue? I’m at a lose and it sits in the driveway.

 

[lawsoncl]

The guy was wrong and you're not the first person to get stung by assuming all the years were interchangeable. 1998 was a changeover year for the transmission. See here for more info - https://naxja.org/threads/everything-you-ever-wanted-to-know-about-the-aw4.1053970/

Also, the AW4 is pretty robust and 95% of the time, the issue is not mechanical. What was wrong with your old one?

 

[Unclewolverine]

Yeah, you just gotta get your wiring right, I put over a 100k on a 01 tranny in my 95. It can work, somethings just not right.

 

[lawsoncl]

It's a bit more than just mating up the wiring to get an 01 to work in a 95.

 

[Jcovatto]

Well the other transmission went out on me on the interstate. I was driving 70 mph and got horrible vibrations in the back end. Next thing I know I’m at 5000 rpms on not accelerating. Then I started smoking out the back. I found a safe place to pull over and popped the hood cause I thought I was on fire. Turned the engine off and it was nothing but coolant and transmission fluid everywhere. Of course the fire department showed up. Well I got it towed home and we let cool down. Checked all the fluids everything looked okay. So we tried to start it and nothing. Had to jump it with our other jeep and it fired up. Everything sounded fine. Kept adding new transmission fluid to get it back to full. I put it in to reverse and nothing. Put it in to drive…. Nothing. Figured we blew the transmission. So that’s when we went and got the new one. Does anyone have the way of how to wire my 97 to make the 99 transmission work or am I stuck finding a 97 transmission?

 

[Unclewolverine]

Well the other transmission went out on me on the interstate. I was driving 70 mph and got horrible vibrations in the back end. Next thing I know I’m at 5000 rpms on not accelerating. Then I started smoking out the back. I found a safe place to pull over and popped the hood cause I thought I was on fire. Turned the engine off and it was nothing but coolant and transmission fluid everywhere. Of course the fire department showed up. Well I got it towed home and we let cool down. Checked all the fluids everything looked okay. So we tried to start it and nothing. Had to jump it with our other jeep and it fired up. Everything sounded fine. Kept adding new transmission fluid to get it back to full. I put it in to reverse and nothing. Put it in to drive…. Nothing. Figured we blew the transmission. So that’s when we went and got the new one. Does anyone have the way of how to wire my 97 to make the 99 transmission work or am I stuck finding a 97 transmission?

I think you have other issues here. Just the tranny going out wouldn't of spewed coolant and fluid everywhere, and shouldn't of made you have to jump it.

 

[Unclewolverine]

It's a bit more than just mating up the wiring to get an 01 to work in a 95.

Yes, you have to spend an extra 20 minutes changing the reluctor wheel and tails shaft housing, but I don't believe this was pertinent to this conversation because I don't think that's an issues with a 97, is it?

 

[lawsoncl]

Output speed sensor changed in 98, so he's got that exact same problem sticking a 99 in a 97.

 

[Jcovatto]

So… can I fix this? Can anyone help? What can I do? I need my vehicle to run.

 

[Jcovatto]

How is this fixed?

 

[Jcovatto]

I have no idea what the regulator wheel is and rail shaft are. With guidance can please someone help me.

 

[Jcovatto]

The vibration is all coming from the rear axle… sounds to me i need to check the dif and maybe put the old trans back in….

 

[Unclewolverine]

I thought it all changed in 97, my bad. There's probably your problem, at least with the tranny then. When you use the dual speed sensor tranny in a single sensor jeep you have to take the transfer case adapter housing off and change the little metal wheel that the sensor uses as a counter that is snap ringed onto the out put shaft, and use the housing off your old tranny. That tranny will absolutely work in your jeep, it just has to be done right.

 

[Jcovatto]

Thank you that is a lot of help! I will let you all know when we try this how it went!

 

[Jcovatto]

One more thing is there any videos or instructions on how this is done anywhere? This would be really helpful because this is my first and probably last transmission…. I know it won’t be but this a lesson learned to always swap out the same years!

 

[lawsoncl]

There are some pictures way down in the thread at https://naxja.org/threads/everything-you-ever-wanted-to-know-about-the-aw4.1053970/
If you have both transmissions side-by-side, you can pull the back end off and compare to see what parts need to be swapped.

 

[Jcovatto]

Thank you for this! I did find where the pictures are supposed to be but I can’t access them.

 

[Jcovatto]

Good afternoon. So as you see we tried to remove the 99 transfer case and swap it for the 97. The problem is that the bolts are so rusty that we can’t remove them. Does anyone have any suggestions going forward or am I just going to have to buy a 97 transmission? This 99 swap on a 97 Cherokee is not working.

 

[Unclewolverine]

Although you do have to remove the transfer case, that's not what you have to swap to make it work. It's the transfer case adapter and the counter wheel snap ringed to the tailshaft.