I blew up the aw4 transmission in my 2000 xj classic np242.
I purchased a donor jeep 1990 np231 aw4 for a good price it has everything, motor trans t case pcm and all that.
is there any special things that i need to be mindful of or change when swapping trans and t case over. Any help will be much appreciated. Thank you!

 

That 1990 AW4 isn't going to work in a 2000.
https://www.naxja.org/forum/showthread.php?t=1053970

Define "blew up". Not shifting correctly or burnt up clutches.

 

reved it up in neutral and put it in drive. Lost drive 3 and only have half of 1•2
So there’s nothing I can do to make it work with that motor?

 

If you pull the fuse for the trans computer, can you shift "manually" with the shifter? (1-2) will give you first gear, (3) third, and (OD) 4th gear with no t/c lockup.

 

Most people are going the opposite direction, trying to put a newer AW4 in an older vehicle. You could open them up and swap the rear output sensor parts, but you'd also have to deal with 2000 trans computer *****ing about the lack of a front input speed sensor. It's much simpler to get a 98+ trans that's a drop-in.

 

There a lot of clunking and grinding when moving it also when I drop it all the way down to 1•2 if I give it more gas it will skip and lost power. I can try that but I think it’s destroyed.