Hey everyone,

I'm cross-posting my write-up over from thespeedfreaks.net so you can have a look too! :-)

I decided to do the swap because I didn't like the auto, sure it’s really decent when it works and driving in town but I felt like it really wasted the 5.2's stock potential and sucked on fuel economy. Also, I hate maintaining an auto transmission, very expensive and such a hassle… Granted, a clutch job is also quite expensive but at least it's clean! lol
My 44RE gave up on me when I towed a trailer with overdrive activated (didn’t know it was bad for it) so it overheated and everything went to hell in the weeks following that until I suddenly lost all gears…

Also: 5-Speed RWD V8… Period.

But first, I am in France. There are no Dodge Ram trucks in my country to salvage nv35xx’s from so that option was simply impossible. I discovered that AX15 swaps were possible and I quickly researched my available options. I actually found out that our European 2.5L Turbo Diesel XJs all had 5-speeds which are… AX15s!! I started looking into this and realized that ZJs also had the diesel option and after some quick research determined that it was actually the same driveline, namely an AX15 manual transmission and NP231 transfer case.
Therefore, most will not be able to reproduce my swap because it involves buying a 2.5L Turbo Diesel ZJ and I believe the option was not marketed in North America…
However I suppose the transmission can be salvaged from many other vehicles including a Dodge Dakota or 4.0 XJs..

I quickly decided that this would be my choice for a swap because buying a donor ZJ for cheap would provide all the necessary and auxiliary parts such as the pedals and hydraulic clutch assembly which otherwise would have cost me an arm and a leg or prove impossible to find!

I found a donor with a bad head gasket and bought it for 500€, it actually was the most uneventful Jeep retrieval of my life: everything worked fine despite the bad gasket, I had no problems making the 300mi journey home! lol


My V8 ZJ, or more technically a ZG because it's an export model assembled in Steyr, Austria, is a 1997 Limited with 170,000 miles. It is stock with no engine or suspension mods aside from WJ front control arms.

Anyway, here's the result!


And here goes!!


PARTS REQUIRED:

Here is a list, all parts assumed SAME YEAR unless otherwise stated:
- AX15 transmission and shifter.
- Dodge Dakota 3.9L V6 5-speed bellhousing
- Dodge Dakota flywheel and clutch master kit
- Throwout bearing (universal P/N 53008342)
- Clutch fork (universal P/N 52107555 or 53006388)
- Pilot bearing (I used the one provided in the clutch master kit)
- Hydraulic Clutch Master/Slave Cylinder Assembly (I highly recommend the stock ZG/diesel/export model P/N 53054360 because it incorporates a connector useful for NSS wiring explained below)
- ZJ Clutch pedal and bracket, smaller Brake pedal.
- Dodge Starter (for your bellhousing)

Optional interior parts: shifter boot, doghouse cover.

I bought the bellhousing from a vendor on car-part.com (American Import Auto, CO - excellent customer service by Shawn!). Make sure to ask for the inspection port cover and all the relevant hardware (block/bellhousing, flywheel/crankshaft, flywheel/pressure plate bolts). I forgot to do so and battled later with hardware suppliers to find it all (see below)...

I bought the starter as a remanufactured unit from eBay, so far so good...

Exhaust manifold is up to you to choose but you need a center outlet manifold because the stock 5.2 one exits just above the relocated starter… :-(

Block huggers are a good choice if you can afford them, I went the cheap route and bought a late 1960s Dodge/Plymouth 340ci center outlet manifold. I can only suggest getting the -albeit very rare- early manifolds because they have large 2.5” outlet ports that match the stock Magnum manifolds. I have the smaller 1⅞” outlet because I didn’t know. It still works fine.

You will have to fabricate your own downpipe but I found it easier to do than I thought, most of the stock Y-pipe can be reused...



THREAD SIZES:

I had a very very hard time with thread sizes because European stores only supply metric hardware and special SAE hardware is only available via an internet suppliers…

Here is this info that I found with great effort!! lol

- Crankshaft/Flywheel: 7/16” UNF
You will need 6 longer 1" bolts to secure the flywheel and flexplate to the crankshaft because the stock flex plate bolts are much too short.

- Flywheel/Pressure Plate: M8x1.25
These bolts were NOT included in the clutch kit and I had trouble finding the right thread size. I thought it would be SAE so I tried 5/16” UNC but they wouldn't screw in right: too small. I finally realized they were M8x1.25 but the threads were ruined. I finally drilled through and tapped them to M10.

- Block/Bellhousing lower bolts: 7/16” UNC
You will need 2 longer 3" (or more) bolts because the stock ZJ bolts are too short.

- Bellhousing/Clutch Slave studs: 5/16” UNC
You will need 2 nuts and washers.

- Pedal bracket studs: M8x1.25
You will need 4 nuts and washers.


That is all the extra hardware you will need. That's what I needed anyway.


REMOVAL OF AUTO:

I’m posting this section because I had a very hard time learning about 44RE removal procedure, I didn’t have an FSM at the time... Since it wasn’t obvious to me I researched it and explain it here.

I started by gutting the interior, it’s not really necessary but it gave better access to the doghouse and also kept everything super clean for future re-assembly. Also I hated the idea of ripping the carpet.
I removed the seats, center console, and carpet. Don’t forget to adjust your seats far enough forwards to uncover the rear bolts before you disconnect the battery…
The rear bolts will be seized up good! I recommend spraying whatever penetrating lubricant you have beforehand to avoid breaking them!! (Happened on the diesel donor, took it as a warning from the universe…)

The transfer case and gear selector bezels are actually a whole assemblies that you can pry and unclip off from the console, don’t start disassembling them layer by layer!! To remove the gear selector knob, you just have to pull it upwards, setting it in 1 or 2 saves you from banging your hands on the dash when it comes off… Pro tip!

For the center console there are 4 screws under the gear shift selector bezel and 2 under the armrest at the bottom of the box.

I suggest removing the carpet to avoid tearing it up and having better access to the doghouse.

Disconnect the cables attached to the gear selector. Underneath, disconnect the transfer case shift linkage from the lever: pry the rods off their bushings with a screwdriver or a wrench…

Unscrew the doghouse cover then pry it off the transmission tunnel to detach it (it is glued).

Remove the driveshafts then all the connectors and breather lines.

Support your drivetrain with a jack and remove the crossmember and the transmission support bracket. Unfasten the transfer case and when nothing else holds onto it (shift linkage?) remove it.

Disconnect all cables and connectors from the transmission. Remove cooler lines too. Remove the starter and inspection port cover.

Unfasten the torque converter from the flexplate by removing the 4 bolts accessible from the inspection port, you will need to turn your engine over by hand to access all of them, I found it easier to do than I thought.

You may start unbolting the transmission from the block, lower the drivetrain slightly to better access the top bolts.
The passenger side bottom bolt was sent from Hell itself because you need to remove the oil filter to extract it. Messy messy messy!!! ;-)

Once the transmission and torque converter are unbolted and all connectors, linkages, cooler lines are off then you may proceed with the removal of the transmission, call a buddy to help you out if you are cheap and don’t have a special lifting equipment because that big lady is mighty heavy indeed!!! Hehehehe

Drop that ATF-gurgling unit to the floor and send it to the goulag, it’s probably broken anyway if you’re doing this swap…

Remove the kick-down cable and gear selector cable. Hello precious weight saving!

Unbolt the flexplate from the crankshaft and set aside for later use…

If I forgot to mention something to remove, sorry… A lot to recall!!!

You should have a beautiful transmission-less engine block looking at you and lusting for a mate… Time to give it to… it? Moving on.


PREPARATION:

Take your Dakota flywheel and remove the tone ring. You should be able to do so with an adequately sized wrench and hammer, pry it off or if you are lazy just cut a notch in it and spread’er whyyyde open!!
We’re doing this so we can reuse the stock flexplate by mounting it with the flywheel so that all will be good in the Crankshaft Position Sensor’s world!! He’ll be oblivious to the change and you know what they say: ignorance is bliss… BAM!



Install the flexplate with the flywheel over it onto the crankshaft using your duly acquired 1” bolts that you will fasten to spec. Check that your pilot bearing fits the crankshaft bore and the AX15’s shaft, you never know! (The copper bearing supplied by the clutch master kit fit both like a charm, the needle bearing, not so much…)
Continue with clutch disc and pressure plate installation using the alignment tool and torque to spec.

On the AX15 side: bolt up the Dakota bellhousing onto it, add the fork and throwout bearing and finally the pilot bearing.
I’d also remove that shift lever if I were you, Bubba…


NOTE: This is NOT my photo, credit to "samwise" at nagca.com. My pilot bearing was a copper ring too only much thinner.

ASSEMBLY:

Check you have all the block/bellhousing hardware, the pilot bearing still on the input shaft and the transmission in gear (so that you can play around with the output shaft to align the input shaft splines with the clutch disc).
Bring a buddy over again, lift it up and mount that tranny!!!
Secure it with 2 bolts finger tight while said buddy is holding it up (do it quickly!) then have him catch a break and fasten the rest of the bolts including your duly acquired longer 3” bottom bolts! Torque to spec and don’t forget your washers! ;-)




Mount your transfer case, be it the original 249 (meh..), a 231 (hey hey hey!) or 242 (lucky bastard...).

For the transmission support you may have to improvise your own solution depending on the origin of your AX15. I reused the diesel’s crossmember and support by extending the transmission support bracket.
Ideally, one should reuse the stock auto support and fabricate a custom bracket for the transmission, it was designed for a V8 engine. Consider upgrading to polyurethane bushings...


Left: The original diesel support was just an inch off... Right: The extended bracket.

Secure everything and install the rear driveshaft although a slightly longer rear driveshaft is preferable in my special eyes. The front stock one will be too long to reuse without shortening.


NOTE: This is not the V8's driveshaft although it did fit. It's just that it was too short in my eyes so I mounted this 2.1L XJ driveshaft which is about 1" longer. Drives fine without vibes up until 120 MPH...


You can now put the doghouse cover back on.




CLUTCH AND PEDALS:

Remove the brake pedal.
If you have one: disconnect and remove the Speed Proportional Steering module because you will have to remove its metal mounting bracket. It is spot welded twice, do what it takes, soldier, but that bracket has to come down one way or another!!!


Left: the diesel firewall. Center: V8 Steering module bracket. Right: ... during the amputation operation, a bit messy...

Once the area is clear you will need to drill the holes for the master cylinder from the engine compartment inwards. There are dimples and a nice circle marking the drill locations. Fire at will.


Left: The diesel firewall. Right: The V8's

You can now mount your clutch pedal bracket.



For the hydraulic line you will need to remove the steering shaft (do it with your steering wheel locked!!!!! otherwise bye-bye clockspring) and unbolt the ABS module to slip the line underneath it. Rest it under the brake booster and feed the master cylinder into its new home.
Secure the the slave cylinder to the bellhousing.
Secure the master cylinder rod to the clutch pedal.


WIRING:

- Reverse Lights

Find your NSS connector (3-pin circle connector) and snip the outer 2 wires, connect (I soldered and shrink wrapped) them to the reverse light switch pigtail connector on the AX15 (upper passenger side). Polarity isn’t important but if you are a perfectionist like me you will match the cables because they are the same colors (on a ZJ AX15 anyway).

Reconnect the rest of the connectors and do what you will with the now useless transmission connectors (Solenoid Assembly and the Output Shaft Speed Sensor connectors, FYI). I’d remove them from the underbelly harness.

- Neutral Safety Switch

You have several options:
#1 - Ground it forever: Permanent Neutral state, you will be able to start in gear but lose cruise control.
#2 - Wire it to a switch: Manually set Neutral state on or off. Can Start in gear. Enables Cruise Control but no automatic shut-off.
#3 - Activated by the clutch pedal. Cannot start in gear. Enables Cruise Control and Cruise Control automatic shut-off.

I reused the 44RE gear selector cable grommet to pass the wire through the floor into the cab.


AVOIDING CHECK ENGINE LIGHT:

Thanks to an accidental discovery I made, I have found a workaround to replacing the ECU with a 5-speed Ram unit because of a Check Engine Light (a risky and expensive solution). It involves wiring the Clutch Interlock Switch (green 2-pin connector next to the Speed Proportional Steering).
It is present on all 96-98 ZJs regardless of transmission type.

I have not yet confirmed the presence of this switch on earlier ZJs (haven’t checked other FSMs or other ZJs). I have been told that early ZJs with the 5-speed and inline-6 do NOT have automatic Cruise Control deactivation or a Neutral Safety Switch leading me to believe that this connector is not present… making this workaround impossible for them… It would be cool if you could check yours and report back!
Anyway, Jeep standardization scores once again! Albeit only for 96-98 ZJs apparently…

For this workaround I highly recommend a switched clutch master cylinder like the ones mounted on all diesel ZJs (see above for P/N).
Normally, the clutch master is connected to the wiring harness and it serves as a Neutral Safety Switch (anti-start feature) as you can only start the engine with the clutch pressed in.
I suppose this fix is possible with another type of switch if you are unable to find or afford a switched clutch master. I haven’t tried but I suppose it should work!

I unexpectedly found this same connector on my V8 ZJ. First I connected the clutch master to this connector just like on a diesel and grounded the NSS. The jeep started without a CEL! If I disconnected it the CEL would pop up.

In the end I tried to keep it as stock as possible and connected the NSS wire to the clutch master connector and connected the second wire to one of the Clutch Interlock Switch’s wires.

It’s as simple as that. Really... I can only start with the pedal pressed, like the diesel and the Check Engine Light never comes on. Saves me from replacing the ECU… ;-)


LEFT: My current setup, the NSS is wired via the clutch master cylinder to the Clutch Interlock Switch connector. RIGHT: The Clutch Interlock Switch in detail.


EXHAUST:

I won’t really talk too much about this part because I didn’t do any of the welding so I feel kind of like a fraud for giving instructions…
Basically, remove your Y-pipe and the driver’s side manifold. Do what you can about the studs, the nuts should be rusted enough so that the studs unscrew from the head. WD40 will make the nuts unscrew from the studs so you choose your course of action.


Comparison of Magnum and 340 manifolds, ports are almost identical but the outlet size will be smaller if you have a 70s manifold (smog laws :-( )

Mount your chosen center dump manifold and fabricate your downpipe! Luckily, a friend had a spare piece of tubing with 2 bends that fit almost perfectly so I didn't have to buy any tubing. A friend with more welding experience made this.

I recommend using a band clamp between the 2 downpipes because otherwise the whole Y-pipe can't be removed! As you can see, mine is a crappy one with cheap chrome paint on it.

It’s a good idea to add an exhaust support to the AX15 support bracket. I cut the stock one off from the auto support bracket and welded it to the stock AX15 bracket. Works like a charm, simply effective.



MISCELLANEOUS:

Don’t forget to reconnect all the remaining connectors to your transfer case such as the Speed Sensor and the breather line.

The ZJ AX15 shifter needs to be slightly extended between the 2 bends. I’d say an inch or so. As you can see I cut it and welded and extra piece of rod in between.


Install the Dodge starter with the 2 ZJ block/transmission bolts because they are the same thread. Extend your wiring making sure to isolate it well from anything, including hot exhaust pipes…!

I have not yet reinstalled the transfer case shift linkage, I’d say it’s possible to reuse the stock linkage with slight modifications.



Stay Tuned for updates...