YJ Trans swap, BA-10/5 to AX-15 ** Write Up - Page 6 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > General Technical Discussions > Engines & Drivetrain > YJ Trans swap, BA-10/5 to AX-15 ** Write Up

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineRIGID LED Light Blowout Sale - All Sizes, All Series, all Stainless Steel Door Hinge Pins

Reply
Unread 03-06-2013, 09:54 AM   #76
lincolnmatthews
Registered User
1987 YJ Wrangler 
 
Join Date: Oct 2010
Location: NW WA, washington
Posts: 101
Great writeup! have just done this conversion on my 87, all good except the roughness from something rubbing or drive line. Thought I would re-read this sticky again for any clues. I don't know if anybody hardly reads this anymore, I may have to send a private mess. to Richmond. But I read when he's almost done he says to tighten up the trans & outrigger, but to leave the outrigger a little loose & not to tighten down real hard. I assume when he says "outrigger" hes talking the rear mount under the TC where the studs stick down thru the skid plate?? right?. I think that this maybe my source, I used the adpt plate from Advance Adpts to re-mount the TC mnt thru the original holes in my skidplate, as I have the early 87 with only one set of holes. I'm also thinking that by using this adpt that it may have raised the whole drive train up by the thickness of this plate, which may contribute to some more drive line mis-alignment??? going to check it out later. My main quest. is what do I leave somewhat loose on the outriggers?? I tightened things down pretty tight including the pos rear mnt from Autozone I just put in, it seems awful hard rubber made in China, I don't know if thats my problem, appreciate any thoughts

lincolnmatthews is offline   Reply With Quote
Unread 03-09-2013, 09:48 AM   #77
Richmond88yj
Eat, Sleep, Jeep
 
Richmond88yj's Avatar
1988 YJ Wrangler 
 
Join Date: Mar 2004
Location: Chesterfield VA
Posts: 2,112
The outrigger needs to be snugged down only. It's meant to move to absorb vibes.

I answered your IM and think you either need an SYE or possibly a MM lift with the TC drop. It's just geometry on the driveline, not the outrigger.

Ernie
Richmond88yj is offline   Reply With Quote
Unread 03-19-2013, 07:55 PM   #78
schwag27
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2012
Location: niles, illinois
Posts: 5
i got the same model - 88 YJ with a 4.2 and gathering info for this swap.... when you did your t-case i am confused why did you replace the input shaft but not the input gear as well ?
schwag27 is offline   Reply With Quote
Unread 03-19-2013, 08:31 PM   #79
planedoctor
Registered User
1987 YJ Wrangler 
 
Join Date: Feb 2008
Location: Florida
Posts: 14
You only need to change the input shaft on the transfer case. The BA-10/5 has a 21 spline output shaft and the AX-15 has a 23 spline(stronger). So rather than change out the trans output shaft, change out the input shaft on the t-case.
planedoctor is offline   Reply With Quote
Unread 12-18-2013, 08:54 AM   #80
LIVEWIRE55
Registered User
 
Join Date: Dec 2013
Location: Crossville, Tennessee
Posts: 1
ok my question is if i can get a ax 15 with the transfer case on it already, would it not be easier to just leave the tc thats already on it, then to buy a input shaft, and breaking down my old tc. Or does it take some modification to use the ax 15 case?
LIVEWIRE55 is offline   Reply With Quote
Unread 12-18-2013, 01:57 PM   #81
planedoctor
Registered User
1987 YJ Wrangler 
 
Join Date: Feb 2008
Location: Florida
Posts: 14
Yes, the NP231 is the same other then the input shaft spline count. If you have a transmission and TC as an assembly you can just go with that. Just be aware there were some changes made to the speedo output on the newer units that might not fit your application. The newer ones have a digital output instead of mechanical.
planedoctor is offline   Reply With Quote
Unread 12-18-2013, 04:34 PM   #82
jimbos76cj
Registered User
1989 YJ Wrangler 
 
Join Date: Jun 2007
Location: Florida
Posts: 433
I'm pretty sure the hole for both units are the same.. You just need the speedo gear from your jeep.
__________________
88 YJ 35's 8.8 rear, family style roll bar, ax-15 external slave conversion, Custom double D fab dash 4" of lift taurus fan, Head light wiring upgrade, MSD 6al, JB conversions SYE, 258 with RV cam, Long tube headers, Borla exhaust. 1"mm, Auto meter gauges.
jimbos76cj is offline   Reply With Quote
Unread 12-21-2013, 07:12 PM   #83
scottmmb
Registered User
1987 YJ Wrangler 
 
Join Date: Sep 2013
Posts: 65
Okay. If i got a 89 ax15, what stock tcase do I need and when I got that will the stck drive shafts fit?
scottmmb is offline   Reply With Quote
Unread 01-18-2014, 04:23 PM   #84
GrEmLiN
Registered User
1987 YJ Wrangler 
 
Join Date: Feb 2008
Location: Southwest, Connecticut
Posts: 128
http://www.jeepforum.com/forum/f19/y...l#post12716287
See post #51 for more information on which input gear to which transmission/tcase combo etc. as well as Advance Adapters p/n's for swap components.

I've long since completed this swap and I'm not subscribed to this thread, so if anybody needs help, feel free to PM me for info.

Scottmmb, if it's just the trans with no tcase attached, measure how far the shaft protrudes from the back of the transmission. If it's flush or if it sticks out .43" (about half an inch), and then count how many splines it has. If it sticks out half an inch and has 23 splines you're in luck, that's the most common, and nearly any NP231J with a 23 spline input should work. As noted in my post, #51 on page 4, there's three measurements to look out for on the tcase. 1.2", 1.7" and 2.1" -- the 1.7 is for 4cyl or automatics, you'll need the 1.2" if your transmission output shaft protrudes half an inch. I don't think the 2.1" input on the tcase will allow proper mating, but I've never tried. If you're going from a manual trans to manual trans then yes drive shaft lengths should be the same. BA10 and AX15 installed are very similar or same in length. At least I haven't had any issues.

Jimbo is correct, if it has a VSS just place your speedo gear and cable in. It can be tricky to catch the teeth properly.

Any questions in the future, PM me I don't bite.
GrEmLiN is offline   Reply With Quote
Unread 01-18-2014, 05:49 PM   #85
jimbos76cj
Registered User
1989 YJ Wrangler 
 
Join Date: Jun 2007
Location: Florida
Posts: 433
I was just tearing into a t-case today to pull the chain for a buddy with a broken one and decided to take pics including how to remove the input gear and swap them out. I'll try to get pics up soon if any one is interested. It was very easy to get it swapped.
__________________
88 YJ 35's 8.8 rear, family style roll bar, ax-15 external slave conversion, Custom double D fab dash 4" of lift taurus fan, Head light wiring upgrade, MSD 6al, JB conversions SYE, 258 with RV cam, Long tube headers, Borla exhaust. 1"mm, Auto meter gauges.
jimbos76cj is offline   Reply With Quote
Unread 01-18-2014, 05:54 PM   #86
jimbos76cj
Registered User
1989 YJ Wrangler 
 
Join Date: Jun 2007
Location: Florida
Posts: 433
Quote:
Originally Posted by scottmmb View Post
Okay. If i got a 89 ax15, what stock tcase do I need and when I got that will the stck drive shafts fit?
You are looking for a 231j from another jeep with the ax-15. Or.. If your lucky you can find one from a xj with a ax-15. No matter what check the spline count before you pick one up. Make sure it's a 23 spline. The other option is to change the input gear on the t-c. If you already have a 231 the gear can be bought for about $100-$125 (I think.. Haven't priced em in a bit) it's really easy to pull the case apart and change it. Took me about an hour to tear one down today to take pics for a write up. Oh and there is a rumor that a few later year ba-10s had a 23 spline t-case. Never seen one but that's the rumor.
__________________
88 YJ 35's 8.8 rear, family style roll bar, ax-15 external slave conversion, Custom double D fab dash 4" of lift taurus fan, Head light wiring upgrade, MSD 6al, JB conversions SYE, 258 with RV cam, Long tube headers, Borla exhaust. 1"mm, Auto meter gauges.
jimbos76cj is offline   Reply With Quote
Unread 01-18-2014, 10:02 PM   #87
GrEmLiN
Registered User
1987 YJ Wrangler 
 
Join Date: Feb 2008
Location: Southwest, Connecticut
Posts: 128
I second what jimbo said, and for what it's worth, instead of looking for a new input gear for my tcase (I used a 92 YJ tcase and 96 XJ AX15) I found a complete tcase, full of water, for $40. Dumped it out, filled it with WD40 and shook it all up, drained, repeat over a couple of days... and it's been working fine for a couple years now.

Also, if anyone is interested, I have a photo gallery up on facebook I can send the link to with a bunch of pictures documenting my BA10 to AX15 swap. The pics are from 2012 when I did the swap but they're still online. You don't need a facebook account to view the gallery. I'm just not too proud of my booger welds and how I ultimately did the transfer case shifter so I'm not about to post the gallery freely yet lol.

If there's a demand, I'll share willingly.
Post or PM.

Also, this might be a good time in this thread to point out for those interested in this swap, YOU WILL NEED A TRANSFER CASE SHIFTER FROM AN AX15 EQUIPPED YJ! An AX5 bracket might work? I have no idea. But the BA10 is not as wide as an AX15, so the tcase shifter bracket will not bolt up properly. You can modify the existing shifter with a little work and planning. I didn't like how I did mine originally but I was likely inebriated at 3am and decided to do the shifter mods then, so I didn't plan very well.


Jimbo, how do you like the Ford Taurus electric fan? Notice a big improvement? How much did it set you back? Which writeup did you follow, if any?

Years and years ago my radiator blew up and I replaced it with a cheap, made in china boogerwelded 100% aluminum radiator from radiatorsus.com or something like that. It was $120-130 shipped to my door, all aluminum with a very good warranty backing it up in case the childlike welding failed. 6 years later it's still working very well, and dropped running temps 5-10 degrees easily. Maybe more my gauge only works when it wants to.
GrEmLiN is offline   Reply With Quote
Unread 01-18-2014, 10:49 PM   #88
jimbos76cj
Registered User
1989 YJ Wrangler 
 
Join Date: Jun 2007
Location: Florida
Posts: 433
Unfortunately I haven't had a chance to get her on the road yet. As for cost a friend gave me 2 fans for free and I wired it with a 80amp constant duty solenoid and 195 on 165 off (I think) coolant switch. I also added in a 40 amp relay and manual off switch I think I have $80 total I to it.

How did you get the t-case to bolt to the xj ax-15? I thought the tail housing was drilled to clock it 10 degrees down on those.

Please forgive my typos or punctuation, I'm in the front seat of a fire truck with a horrible tire shake.
__________________
88 YJ 35's 8.8 rear, family style roll bar, ax-15 external slave conversion, Custom double D fab dash 4" of lift taurus fan, Head light wiring upgrade, MSD 6al, JB conversions SYE, 258 with RV cam, Long tube headers, Borla exhaust. 1"mm, Auto meter gauges.
jimbos76cj is offline   Reply With Quote
Unread 01-19-2014, 12:41 PM   #89
GrEmLiN
Registered User
1987 YJ Wrangler 
 
Join Date: Feb 2008
Location: Southwest, Connecticut
Posts: 128
Quote:
Originally Posted by jimbos76cj View Post
I think I have $80 total into it.

How did you get the t-case to bolt to the xj ax-15? I thought the tail housing was drilled to clock it 10 degrees down on those.

Please forgive my typos or punctuation, I'm in the front seat of a fire truck with a horrible tire shake.
Hahah, that last part made me chuckle.
That's a great setup for $80!


Ok I'll post some pictures up to answer your question. I drilled new holes in the XJ transmission.


I was fortunate enough to have a YJ and an XJ AX15 on hand. The YJ AX15 was known to grind, and was internal slave. The XJ was newer, also grinds a little bit, cleaner and above all external slave. The bosses are there on the internal slave trans to punch the holes out and use an external slave. Hard to see in this picture but I started making a template from one and applying it to the other. A transfer case or BA10 could theoretically be used to make this template. This happened to be easiest for me.

XJ transmission, note the location of the holes. If there's "meat" to the right of the holes its an XJ. If there's meat to the left, it's for a YJ.

Using a ballpeen hammer and some shirt cardboard (like you get stuffed inside a dress shirt) you lay it over the holes and tap it to make a mark on the cardboard. It's like a hole puncher almost.

Automatic center punch + Sharpie




GrEmLiN is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.