Ax15 swap into 83 j10 360

[dyermullet]

Hello everyone,

I am looking for some guidance so I can try to complete this swap as efficiently as possible time wise. I am leaving in about a month on a year long camping trip and need to get the trans sorted out. I read a lot of threads on this but most are i6. Or discussion on performing the swap but never actually follow through. I am on the road right now and want to confirm/compile some of this research

The truck is a 1983 j10 360 t177 with np208. The t177 has developed a faint bearing noise and when you get on and off the throttle the shifter is moving forward and backward. It appears to be thrusting internally. It does it slightly in 1 &2, and it is much worse in 3 &4. I rebuilt the trans myself 2,500 miles ago. The top cover needed replaced when I opened it up gears and shafts looked up but when I broke shafts down found rtv blocking oil circulation passages. Before the rebuild I personally only put 3 miles on the trans until the shifter jammed up and I rebuilt the unit.

Normally I would take another crack at this trans but due to time I just want to replace.

I was researching the ax15 swap. I want to keep the manual clutch linkage, not interested in hydraulic swap. I have found advanced adapters has an adapter to fit the ax15 to a t177 bell. The should allow ability to keep the mechanical linkage. Anyone have feedback on using the advanced adapter for ax15 to replace t177.

I need a new pilot bushing because input shaft ia larger diameter .

I prefer to keep the np208. So I am going to need spacer between trans and tcase, because output shaft on ax15 is longer. Is this correct? Looks like Novak has adapter for ax to np 208.

Is there a cable speedo version of nv231? Might be simpler/cost effective to get one of those instead of a $300 spacer to keep the np208?

Does anyone know the how much different the shifter position is on ax15 compared to t177 with the spacer?

Any ideas on where the trans cross member will land? Will any of the existing bolt holes work out?

Trans mount - do they interchange?

Ax15 has two different clocking on the case pattern? Xj is better match, wrangler is too flat of mounting is this correct?

Shifter - just modify what comes with the trans?

[Yeller]

231's from a YJ, XJ, and early TJ were all mechanical speedo and there are enough gears available for most any gear/tire combination. I prefer mechanically the 231 to the 208 but not apposed to it.


shifter location should be close to the same. I would just modify what comes with it for a shifter. With the Novak bell adapter, clutch linkage should stay the same. That's about all I can intelligently answer.

[dyermullet]

Thank you. Does Novak have bellhousing adapter? I can't only find a complete bell made for hydraulic retrofit on my phone. I did find advanced adapter had adapter that kept my current bellhousing. I will call novak and advanced adapter tomorrow.

I rebuilt a 231 years ago but don't remember the specifics. Thanks for the heads up they are mechanical speedo. I will look into them closer.

The main reasons to use the 208 is because I have it. Does not use a slip yoke. And I opened it up the fluid was clean and it was perfect inside.

I will have to price a sle for a 231. But I am sure I could get a junk yard unit and replace any bearings for cheaper than Novak wants for the ax15 to 208 adapter.

I like the idea of a 231 if had trouble on the road can get a replacement easily.

[dyermullet]

Looks like 231 only used mechancel speedo 88-91.

Does anyone know if the speedo drive from my 208 will fit the 231?

So far can't find an 88-91 tcase local but will keep looking.

[Yeller]

The later ones still had the drive, it just drove a signal generator, you still adjusted the speedometer by changing the gears through 2001 or 2002 can’t remember the change exactly. You just unscrew the generator and connect your speedometer cable, it is the same thread and drive size.

[dyermullet]

Okay makes sense.

[dyermullet]

Just giving an update. Everyone is out of stock on new AX15.
Was able to buy 2 used ax15 semi local. Tore them both down, found problems in both of them. Chipped teeth on one and rusty pitted gear teeth. Second one that appeared to be factory sealed had had the synchro springs and keys assembled wrong on both hubs. Third gear dog teeth were completely destroyed, and all 4 synchro rings were hammered. Picked the best of the two ordered rebuild kit and the parts I need.
Went with the advanced adapters kit for AX15 to the T177 bell. It showed up in the mail yesterday, and it missing the bearing retainer. Very disappointing. Sent them an email and will call on Tuesday.
Both of the transmissions are from TJ. I got a spacer/clocking ring for trans to tcase. Haven't decided if I am going to redrill the trans and use only as a spacer or use clocking ring. I am leaning towards re drill trans since I am waiting on parts.
Right now I am going to try to keep the NP 208 since I have it and it is perfect condition. If for some reason that doesn't work out I can easily grab a 231 from the local pick a part yards.

[devildog80]

Kudos to you for diving in and rebuilding trans at home.

Would be nice to see a step by step AX15 rebuild thread (or is there one out there already), as some facing the same issue think about rebuilding one of these, and darn near wet themselves at the thought. Sadly most let their trucks sit, until a plug/play option comes along they can work with, and at current supply dates these trucks will probably sit for a year or two before it catches up. No fun to own a truck that just sits that long waiting for parts.

Sadly there are few shops with skilled staff, that even know where to start at this level of expertise, and no guarantee if they would even do it right.

Have courage and dive in

Just giving an update. Everyone is out of stock on new AX15.
Was able to buy 2 used ax15 semi local. Tore them both down, found problems in both of them. Chipped teeth on one and rusty pitted gear teeth. Second one that appeared to be factory sealed had had the synchro springs and keys assembled wrong on both hubs. Third gear dog teeth were completely destroyed, and all 4 synchro rings were hammered. Picked the best of the two ordered rebuild kit and the parts I need.
Went with the advanced adapters kit for AX15 to the T177 bell. It showed up in the mail yesterday, and it missing the bearing retainer. Very disappointing. Sent them an email and will call on Tuesday.
Both of the transmissions are from TJ. I got a spacer/clocking ring for trans to tcase. Haven't decided if I am going to redrill the trans and use only as a spacer or use clocking ring. I am leaning towards re drill trans since I am waiting on parts.
Right now I am going to try to keep the NP 208 since I have it and it is perfect condition. If for some reason that doesn't work out I can easily grab a 231 from the local pick a part yards.

[dyermullet]

I have a lot of experience with this stuff. I rebuilt the T177 about 2,000 miles ago it is my first manual gearbox to fail right away after a rebuild. Nothing seemed to be too be wrong or go together poorly but it has horrible amount of thrust, didn't get to drive it before the rebuild maybe the thrust was always there. I will probably tear it down again in the future and inspect it.

So far the only thing intimidating on the AX15 is all the interlock balls and pins, and they way they all just fall out when taking it apart. Not looking forward to finding the correct assembly order. Also the 3rd gear hub press fit was very very tight onto the main shaft. I have a 12 ton harbor freight press I have been using for 10 years, I kind of sprung it getting that gear off. Will have to see if it holds up through reassembly. Harbor Freight had 25% off today, I probably should have went ahead and bought a new one.

[devildog80]

Since I commented earlier, I did check online, and there are some video's out there for rebuilding the AX15.

Nice to know we have info like this now, as decades back, we would have been at the local NAPA looking through their books

[dyermullet]

I used two of the online videos for reference. That and I found the section of the factory manual that covers ax15.

I still need to read the reassembly section of the manual. I think the biggest difficulty will be getting all those interlocks back in place. It has 4 shift rails with the interlocks and it felt like an extra detent ball came out of the r &5 rails that might be one that floats. I have read this transmission has a lockout from 5 to R so I assume that is what this extra ball is.

[devildog80]

I would sure find where it goes according to the factory manual, before putting the trans back together.

Extra parts on a project like this is not good

[dyermullet]

Finished the rebuilt, only have a few parts left over, but they are small so probably not important.

[dyermullet]

Today I am comparing the fit up of my 208 transfer case to both of these transmissions. 208 to the T177 has 1 3/4" spline engagement from the output of the transmission to input of Tcase. The AX15 will have 1 3/16" engagement. ( these measurements are the amount of splines exposed past the seal. The amount of spline engagement behind the seal for each is fairly consistent.)

Should I be concerned about a loss in strength by giving up 1/2" of spline engagement? The truck is a stock 360, 3.31 gears, 31 x10.5 tires. Will be hauling some camping gear in the bed, and towing a 2,500 lb MAX fiberglass camper.

I am going to keep moving forward with fitting the AX15. I will check back later today to see if anyone has experience with this.

[Yeller]

No reason to be concerned that’s more than sufficient engagement

[devildog80]

DOH...

Finished the rebuilt, only have a few parts left over, but they are small so probably not important.

[dyermullet]

Crossmember in stock location will interfere with the front driveshaft. But it is very close to lined up with the Trans mount pad on the ax15.

In the rear position should be fine with driveshaft. Will need an extension to connect Trans mount.

I am getting short on time so ordered a few parts. Going to run the rear Crossmember position.

[dyermullet]

Ended up with cross member in rear position.
Used the Novak mount because no time for anything else. Changed out the hardware that came with the Novak mount. Grade 5 lock nuts use different size socket, added washers to the bushings. (I think a tj mount would work but the Novak mount came in the mail first so that is what I used).
Used advanced adapters, adapter for ax15 to stock bellhousing. Kit arrived missing bearing retainer and only had half the paperwork. Had to wait for missing part to be shipped and got the instructions off website. Was not impressed.
Redrilled ax15 to a Cherokee drop angle.
Used an advanced adapter "clocking ring" made for an atlas as a spacer between ax15 and np208. Installed longer studs in transfer case and just used ring as a spacer.
Extended tcase shifter linkage.
Replaced ebrake cable with one from a 6 cylinder.
Kept stock clutch linkage.
Was able to use stock shifter boot.
Cut t177 shifter base and ax15 handle. Welded together. Gave a stock look.
New drive shafts.
Have about 1200 miles on it so far, all towing our Casita trailer. No problems from the Trans setup. Wish I would have done the conversion in the first place instead of wasting the time and money rebuilding the t177.

[Stuka]

Glad it’s working out well for you!

[dyermullet]

I had taken some pictures but lost all of them. In the future I could take some new ones.