89 YJ Trans trouble BA10/5 to AX-15 Swap

  • Well on Saturday morning me and the boys decided to take the jeep down to Rising Sun to the bank and the barber shop. I went to back in a parking spot and the shifter wouldn't go into reverse so I did the only thing I knew to do was pull into the spot across the lot and bounce off the curb and drift back into the spot I wanted. Went in and got my haircut and when I went to leave the jeep wouldn't shift out of second thought I could get it going and maybe things would right themselves :driving: . BUT of course nope..... so I reached out to Bob :help: (sandtosand) and he came to rescue me with the trailer. While waiting on him to show up I did some research and see that the Peugeot BA-10/5 is problematic and the preferred tranny is the AX-15.





    My question is have any of you done this? Likes? Dislikes? Any major hurdles?
    Any certain year AX-15 better or worse?

  • Close to a direct swap. Issue is gonna be finding a good ax15. They r prone to start grinding in 3rd around 100k expecially when they swap the fluid and dont use an ultralow sulphur oil like syncromesh. Things to watch out for and some facts....


    The were behind the 4.0l from 89-2000
    In 94 they went to an external bellhousing which is more desirable
    In, i think, 92 the input shaft changed so the pilot bearing may be different
    U will need to swap the input on the tcase to a 23 spline or get the case with the trans
    U will need the tcase shifter bracket from the ax15
    Advanced adaptors has the parts if u want to use the older master cylinder with the external slave or u can drill new holes in the firewall for the newer master
    Ax15 and ba10 r the same length
    Clutch is the same but pilot may have to be changed
    Trans bracket is different but the rubber mount is the same, u can mod the skid or get a newer style one


    It might be a little more wok but i would look into swaping a nv3550 fom a post 2000 tj. They are newer and last longer.

  • I did it in my old MJ prior to swapping it to an AW4. Been awhile but Aaron detailed most/all of the gotchas pretty well. I ended up using a 23 spline 231 as mine was 21, it was still internal slave so that swapped over, replaced clutch/pilot bearing at same time so was a non-issue as I bought ax-15 specific parts, hacked up tcase shifter bracket as donor didn't have one, and my trans mount was shot anyway so replaced w/ new ax15 unit. Good luck!


    --Ian


  • Do the drive shafts need to be re-sized?


    No as i said they r both the same length.

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