[jb4]

part 1 of my AX15 rebuild

Background:

I bought a '98 TJ Sport from a friend in late January for $1000. I was able to get it so cheap because he didn’t want to incur the costs associated with fixing it. It had broken down on his way back from Indianapolis one weekend and from what he said it “just needed a clutch,” when things seem to be too good to be true, they normally are. it’s a pretty sweet ride – A/C, dual tops, 30” tire package, a couple spots of rust in the body, but overall its in great condition. It’s the second TJ I’ve owned (I had a ’97 2.5L from 97-02 and traded that in on a WRX, I’ve also had an ’01 WJ limited which I loved)

I started poking around here on JF for clutch threads and decided on ordering a LuK clutch and flywheel. I also came across the 4x4xplor link for the replacement procedure (I picked up a copy of the FSM to add some insurance as well) so I figured I’d go ahead and do all this by myself in my garage. Until this point the most serious repair work I had undertaken was a water pump on a 302 baby Cleveland Ford. But I work for a dealergroup and have access to not only an awesome parts bin and tools but a group of Techs who are more than capable and can at least point me in the right direction. I do have air tools and a 18v cordless 1/2” Snap-On impact gun that I used for removing lug nuts and the skid plate nuts (had to cut off/drill out two of those and followed a thread for installing nutserts that I found on JF as well.) But other than that I’m doing this all with hand tools on a work bench. I know at some point I’ll need a press and when it comes to that I’ll just take the bits I need to work.

When I had the transmission separated from the engine I was treated to a broken throwout bearing clip which I assumed to be the issue. As you can see the clutch, for having 117k miles on it is in pretty good shape, so at the time I assumed the clip was the only issue. I put the new flywheel on, installed the new throwout bearing and clutch, drained all the fluids (which didn’t indicate any issues either – no metallic bits came out as I drained everything) and bolted it all back up.




I also ended up replacing the starter on it as the Jeep had sat for three months before I bought it and the magneto had frozen. When I got in it to start it up victoriously it started right up and I was excited to get it on the road after having it on stands for two weeks. Well it didn’t move, at all at first until I tried fourth gear, then I had to slip the clutch a lot but it finally moved a couple inches on its own power. It wouldn’t move in reverse either.
I had a friend who was a tech at our Porsche store and who now works in the transmission R&D department at Case Heavy Equipment Manufacturer take a look at it – obviously he didn’t like what was going on and said the best thing to do at this point was to tear it all apart. I was bummed but considering I had at most $1800 into it with the “cheap seats” I bought from the JF thread, herculiner, fluids, clutch and flywheel, I figured whats wrong with having to spend a couple hundred dollars on the rebuild or the ~$1000 on a junker unit. It would also prove to be one hell of a learning experience.

Tear Down:
So I began to tear it all down again. At least this time I was able to get the whole thing separated and out from under the Jeep in three hours versus the ten it took me the first time. Here it is as it came out from under the TJ



I began by removing the front driveshaft so it would be a bit easier to manhandle as I dissected it further.


And I also removed the tcase linkage so as I was rolling it around on the floor it wouldn’t muck it all up


I also removed the bellhousing bolts at this point – they’re the blue ones in the pic below


Now I could start to break apart the transmission from the transfer case. There was one bolt that was a major pain in the *** to get at – so if you plan on doing this yourself I highly recommend ratcheting box wrenches – which I didn’t have.

[jb4]

After I had all of the bolts removed the two units came apart pretty easily, no pry bar required




At this point I was able to pick the transmission up and put it on a workbench I moved up to the garage for the remainder of the job. Now I started on actually disassembling the trans itself. I removed the shifter retaining bolt and while the FSM said to use a magnet to pull the shaft out of the hole I didn’t have one on hand so I used a couple different small screwdrivers to push the shaft out through the opening until I could grab onto it with my hands. I had to rock the whole assembly back and forth while pulling on the shaft but I was able to get it out.




I also removed the reverse-lockout ball and spring, you can see them here next to the removed shifter and shaft.


And I also removed the reverse light switch as well


Now I removed the throwout bearing retainer – the red circles in the picture

[jb4]

Now I rotated the transmission onto its other end and strapped it down so I could get some good leverage on the bolts for the external housing. It helps to have a drip pan under the work bench to catch the extra gear lube….




After removing all of the bolts all it took was a little bit of prying to get the cases separated





Now with that all apart I could remove the retaining clips that were holding the remaining case to the intermediate plate

[jb4]

With all of the cases removed you can see all of the wicked carnage that has occurred.







I have a feeling that my friend just tried to jam the trans into gear – the bluing on the shaft where there used to be gears indicates that it got extremely hot – also notice that the synchros aren’t exactly level anymore.
It looks like I’m going to order a rebuild kit I found on ebay which includes the synchros, and seals. I’m also going to order all of the bearings for the trans, and once I dig through the parts fiche I’ll have to order that gear set that is now destroyed.

I hope you all enjoyed this so far as I know I have. I’ll update it with what I ended up ordering, the cost of everything, and then hopefully when I get it all together. I plan on cleaning everything too so there should be some nice pictures coming up

-Jb4

[saxart]

This is a fantastic post. I look forward to seeing your progress!

[jb4]

sorry for bumping my own thread here but I'm wondering if anyone knows of a good place to buy trans parts online?

specifically - has anyone bought anything from cyberjeep.com? they seem to be on the low side for parts pricing -

eg - the counter shaft I have to buy is $216 from them and almost $400 from the dealer. because if the piecemeal parts end up creeping towards the $800 mark I'm probably just going to buy a reman unit from the dealer.

[RLD831]

I have a similar problem on my AX-5. Except it's only the gear on the input shaft and the gear on the countershaft. Only problem is the gears that are broken are part of the shafts so replacements will be expensive. The rest is perfect with 40K miles on it. My plan is to gut another AX-5 with blown synchros and take the shafts I need. Maybe you could try that along with a synchro/seal kit.

[jb4]

where do you plan on finding an AX5? I've called a couple junkyards today and the used AX15's they have are ~$900 and a reman from the dealer is $1300

otherwise that is the same problem - countershaft is one piece, and the 1st(?!) gear on the input shaft plus some misc bits needs to be replaced.

[RLD831]

I have 3 AX-5s at my house. One came with my Jeep and two are from junkyards. Mine broke, the second one had no synchros, and the third one I'll be installing tomorrow. I hope it works fine. It will be temporary though, because my plan is to rebuild my original while that one is getting me around so I have a working AX-5 with 40K miles on it as opposed to a junkyard transmission with over 100K. Besides if the third transmission works fine, I can sell it on ebay when I'm done with it.

EDIT: Have you pulled the countershaft out yet? That is my next step, but I was going to wait until I had both transmissions ready to be Frakensteined before I went too far with the disassembly. I was just wondering if you had any tips or tricks or even a mini writeup for it. Pics like yours are always better than a service manual.

[jb4]

I actually plan on doing some more work on it tonight - I'll post it up as soon as I do.

[RLD831]

Thanks. If I have time after school and my transmission swap tomorrow, I may start hacking up the extra AX-5s. I'll start taking some pics to put up when I do. Our transmissions look almost identical inside so it should be a very similar process.

[jb4]

disassembled more of the transmission last night

removing the screw on this side circled and red, and then the one on the other side allows you to remove the reverse shift fork assembly




and then on the other side you can remove the three detent screws/springs/balls, loosen the shift fork setscrew and then slide the entire rail out and remove the fork itself.



removed fork, shaft, and reverse shaft



now you can remove the two select-fit snap rings (red lines are pointing to them) from the counter and input/output shaft. The FSM says to use a gear puller for the 5th gear assembly, and I was about it but they're not pressed on very tightly so I was able to use two prybars at 180* on the assembly while someone tapped on the countershaft.

[jb4]

the 5th gear assembly came off and here is part of the synro setup for it.


the countershaft will slide out now, and then you can remove the plate that is holding the input/output shaft to the intermediate plate. I didn't take a great picture of it but you can see two of the four bolts circled in red



once you have the plate removed, remove the remaining shift shafts, forks, and detents and slip out the reverse idler and idler shaft.




you can now hit the input/output shaft out of the intermediate plate. Here is a picture of the input shaft separated from the output shaft and its next to the countershaft - to separate the input/output shaft all i did was place the portion of the shaft that was missing the teeth into the work bench and hammer on the other shaft lightly while rotating it


here's the empty intermediate plate



now that its all disassembled I can go through the shaft with the parts microfiche and start to pick out everything I need - but realistically I'm going to replace the countershaft and all of the gears. You can't replace one part of a 'pair' without doing the other one - well at least if you want to do it right that is.

I'll post the fiche scans when I get them all set...

[jb4]

Update:

well after making some calls a new trans from the parts counter with my dealership discount is $2300, they apparently dont sell remanufacturered ones.

Pricing out the parts at the parts counter to rebuild is $1800
Pricing out the parts from cyberjeep is $1500
Pricing out the parts from Tellico is $1300

a rebuilt unit from Tellico with a 12/12 warranty on it is $1100 with no core charge and $62 shipping so as a result of the price and the warranty I'm going to just buy one from Tellico.

Ordered it this morning should have it by end of next week.

[Jerry Bransford]

Nice writeup, beautiful photos too! Yeah you made a good decision, $1100 for a rebuilt AX-15 is very attractive compared to the costs you found of doing it yourself.