Transmission swap

[cquinnball]

I have a 1989 Comanche that was converted from a 2WD auto to 4WD 4x4 and the PO cut a much larger hole in the floor than needed likely to make it easier for themselves.  As we know, that makes things more difficult for the new owner.  I am looking to build up from the top of a BA10/5 to fit into a full size console.  I do have an AX15 as well and plan to switch to it one day.  Would someone be able to help me with what parts are needed and if I will have to buy them used or if i can get them new meant for another model Jeep?  I added a picture below so you can see the hole.  I think i need an inner boot, shifter floor plate, bezel, and outer boot.  But i am not sure what is compatible in terms of parts from other models.  I really hoping to find the correct shifter floor plate to see if i need to weld any remaining holes.  The goal is to fit the 4x4 shifter and the manual shifter into a full size console.

 

Thank you in advance!  

[HOrnbrod]

It's hard to see anything in that dark picture mate. 

[cquinnball]

Maybe this one is better?

[87MJTIM]

There are lots of thread on CC with the parts list and steps to perform.  I did the swap on mine several years ago and made a thread.  (Sadly, the pictures were uploaded on photobucket and the links were broken.)

 

Several items that come to mind immediately (assuming you have a BA 10): 

 

A tcase that mates to the AX15 (the one with the BA will not fit)

AX15 trans mount and cross member (again, the ones for the  BA10 will not fit.)

You don't say if your AX15 has the internal or external slave cylinder.  This is important not only for the slave cylinder, but also for the clutch kits.

The tcase shift linkage for the AX15 (you can modify the BA to work or purchase after market shifters)

Depending on the year of the AX15, the input shaft tip size changed from ~1/2" to ~3/4".  You would have to change the pilot bearing/bushing. (See changing clutch kit above.)

 

Others may add to this list.  Good luck.

[Eagle]

My '88 4.0L MJ had the floor butchered by a previous owner. I went to a junkyard and had them cut out the section of an XJ tranny tunnel that surrounds the shifter, along with the screw-in cover plate. I haven't put it all together yet, but I think just cutting the section out of a junked XJ is the way to go.

[Minuit]

Uh, wow. That takes previous owner hackery to a new level. I'd have to agree with Eagle here. That part of the floor is complex enough that welding in a donor section from an XJ is probably the way to go.

[Eagle]

Welding would probably be better, but covering up an enlarged tranny opening isn't a structural repair. I was going to use either mastic or construction adhesive, and screw the repair panel over the transmission tunnel. The separate piece that encloses the factory opening for whatever transmission you have is attached with screws anyway.

[cquinnball]

Thank you!  That’s what I’ll do. Does a combination of a BA10 with a NP231 put the shifters in different locations than an AX15 and a 231?  As of now it seems as though a full size console does not fit over the shifter and 4x4 shifter properly. I was thinking of swapping in my ax15 and 231 now. 

[Jeep Driver]

3 hours ago, cquinnball said:

Thank you!  That’s what I’ll do. Does a combination of a BA10 with a NP231 put the shifters in different locations than an AX15 and a 231?  As of now it seems as though a full size console does not fit over the shifter and 4x4 shifter properly. I was thinking of swapping in my ax15 and 231 now. 

TC shifter is not dependent of the transmission, regardless of which transmission. It should align with the console. 

 

Just so you know, whatever you do, however your do it, you ain't doing it in one day. 

[87MJTIM]

Both the AX15/231 and the BA10/231 line up with the factory trans-tunnel/console opening.  There was not need to cut the floor.   If the PO cut the floor when he/she did the 4wd conversion makes me think he/she "took some liberties" with the swap.  You should check the work to make sure nothing is F'ed up.

[Eagle]

15 hours ago, cquinnball said:

Thank you!  That’s what I’ll do. Does a combination of a BA10 with a NP231 put the shifters in different locations than an AX15 and a 231?  As of now it seems as though a full size console does not fit over the shifter and 4x4 shifter properly. I was thinking of swapping in my ax15 and 231 now. 

 

Same console, same console inserts.

 

Is it possible that that transmission and/or transfer case in your vehicle didn't come out of an XJ or MJ? The tranny and transfer case in my '88 4.0L came out of a YJ, which is why the previous owner butchered the floor.

[87MJTIM]

The YJ transmission clocks differently than an XJ/MJ trans.  From what I've seen/read there would be no need to cut the floor, especially up that high.

[Minuit]

They probably hacked at the floor to make it easier to get at the bolts on top of the bellhousing, if I had to guess.

 

If they were dumb enough to do that, they probably screwed up plenty of other things along the way.

[saveevryjp1998]

36 minutes ago, Minuit said:

They probably hacked at the floor to make it easier to get at the bolts on top of the bellhousing, if I had to guess.

 

If they were dumb enough to do that, they probably screwed up plenty of other things along the way.

I second what he said since the last 3 ax 15's I've pulled from junkyards myself were done that way. I figured out that trick when It was January in northern Indiana, a foot of snow and ice. The truck was sitting frozen on ground without wheels. The sawz all made record time of it and I've done it that way ever since.

[Eagle]

1 hour ago, 87MJTIM said:

The YJ transmission clocks differently than an XJ/MJ trans.  From what I've seen/read there would be no need to cut the floor, especially up that high.

 

The YJ transmission doesn't "clock" at all, and neither does the XJ/MJ transmission. The transfer case in the YJ aligns ("clocks") differently relative to the transmission than the XJ/MJ version. Also, the YJ transfer case shifter is totally different from the XJ/MJ linkage, and that's why the doofus who had my truck hacked the floor. He kept the YJ shifters ... both the transmission shifter and the transfer case shifter.

[87MJTIM]

9 hours ago, Eagle said:

 

The YJ transmission doesn't "clock" at all, and neither does the XJ/MJ transmission. The transfer case in the YJ aligns ("clocks") differently relative to the transmission than the XJ/MJ version. Also, the YJ transfer case shifter is totally different from the XJ/MJ linkage, and that's why the doofus who had my truck hacked the floor. He kept the YJ shifters ... both the transmission shifter and the transfer case shifter.

Perhaps I did not choose the correct terms.

 

The studs on the tcase are in the same position on whether it came from a MJ/XJ/YJ.  The "clocking difference" is the location of the holes drilled on the backing plate of the trans.  These hole locations will cause the tcase to clock differently.  (Lots of youtube videos on drilling new holes to align the tcase between models.)  If the PO pulled the trans from a YJ and didn't drill new holes, this will cause the clocking diff I was bringing up.

 

As Minuit brought up, the PO prob cut the floor to access the upper bolts.