Transmission Option?

[BustedKnuckleJK]

So as I progress in piecing the MJ together, the BA10/5A, has decided to turn itself into a martini shaker. I'm not heartbroken, it's the reason I got the truck for free by popping a new clutch in it. And I know it's stretched, something they were nutritious for, as 1st, 3rd, and 4th are all a waiting game until you can engage them without grinding anyway.

 

So, the thing is 2wd. And I'm of the mindset of if I'm going to lug another transmission under it, may as well go all out and do a full driveline swap. D30s are a dime a dozen in my area, heck there's 4-5 listings locally of D30/D44 package deals for under $400. Driveshafts I'm not worried about, as there's a driveline shop in town I've used before to make driveshafts pretty cheap.

 

My trouble is, which transmission to go with. I can find 42RE all day long, but I'm not a huge fan of them, plus making a TCM work in a Renix era rig is just out of my wheel house. Ultimately, I'd love to have an AX/15 or NV3500 in it, and both are available, with the NV's out of JKs being a bit more plentiful than AX15s that are demanding a pretty penny.

 

The Comanche is a cheap rig, so I'm looking for cheap options. This puts me into old XJ autos, which isn't a bad thing. I'm obsessed with Aisin AW-4 transmissions, as in all my XJ's, I never once had an issue. But, I'm a bit fuzzy on when they started, I want to say 93.

 

Anyway, I found a Facebook listing about 3 hours away from me, a kid is selling an auto trans & np231 t-case out of a 91 XJ. He had it listed for $250, says it was fine when he pulled it, but he used the XJ for it's engine only, and sold off the axles. Obviously how true that is up for debate, but I messaged the guy anyway. I asked if it was an AW-4 transmission, to which he replied "No, it's 2wd, 4wd, not all wheel drive." So it's clear he doesn't seem to know which model it is either. But, just in a two minute conversation, he took another $50 off, saying he really needs it out of his garage at this point.

 

So basically, an unknown auto & t-case for $200. But, I'm not sure of the fitment/control for it. It "should" bolt up if it was out of a similar Renix era XJ, and the only money I'd be out really is what I have into the new BA10/5a clutch kit, clutch master, and u-joints.

 

So, thoughts, opinions? Thanks in advance, and I'll be doing some more reading tonight on the matter. 

[FrankTheDog]

AW4 arrived with the Renix 4.0 In 1987, I have one with a NP242 but I’m 1,500 miles away.

[Jeep Driver]

If you do go with the auto (mistake) just know that the pedal assembly has value, there are guy here who need those. 

[Limeyjeeper]

AX15 is a surprisingly strong trans. NV is good but non Chinese parts are difficult to find if you need to rebuild.

Sent from my SM-G955U using Tapatalk

[Warren Mohler]

I to am interested in replacing my Peugeot clamshell tranny as I know they are problematic I was considering AX15 does any one know if clutch kit will bolt to my existing flywheel is input shaft spline the same? will I need new drive shafts? what would be needed for this swap?

[87MJTIM]

51 minutes ago, Warren Mohler said:

I to am interested in replacing my Peugeot clamshell tranny as I know they are problematic I was considering AX15 does any one know if clutch kit will bolt to my existing flywheel is input shaft spline the same? will I need new drive shafts? what would be needed for this swap?

 

The input shaft tip for the AX15 change from 1/2" to 3/4" in 93.  This happened when Jeep switched to the external slave cylinders.  So, the pilot bearing will depend on the year AX15 you can find.

 

For a clutch kit, get one to match the trans.  If you have an internal slave cyl, you can use the same clutch kit as the BA10.  With the external slave cyl, get a clutch kit to match that one.  (Ask me how I know.)

 

Your flywheel goes with your engine electronics: Renix vs. HO.  So, which ever FW you have, keep it.

 

Your existing drive shafts will work.

 

Get the tcase that came with the AX15.  The BA10 has a 21 spline out put shaft.  The AX15 has a 23 spline shaft.  The tcase has to match the trans.

 

Also get: the trans cross member, trans mounting brackets, and the tcase shift linkages.  The cross member and mounts are different between the BA and AX.