PDA

View Full Version : ZJ AX15/NP231 swap



gonecheenin
12-27-2005, 08:03 PM
(I will edit & fill this in more as i can to make it as complete as possible with part#'s, possibly including pictures also if i get around to it-LOL)

Manual tranny swap into a 93-98 ZJ

(This was done on my 95' 4.0L select-trac Grand Cherokee with a 42re trans, dana 35 rear & LP30 front sitting on a 3.5RE lift)

--------------------------------------------------------------------------------

I personally cannot justify a $2000.00 transmission rebuild for the Grand

thats one of the reasons i decided to go this route (not that it will be cheap either unless your a good scavenger, but at least when i'm done putting in a stick i will feel confident in it's longevity and it shouldn't cost quite as much as the automatic rebuild bill would)

& ultimately I prefer the driving experiance, control, & fuel mileage i get from a manual transmission


On to the driveline specifics;
---------------------------------------------------------------------------------------

The hole for the slave cylinder to mount in is already there covered with a block off plate on 93-95', you can see it easily right on the firewall between the drivers inner fender and the brake booster
96-98 it is marked but needs drilled out
The studs for the upper part of the clutch bracket to bolt to are under the dash on all i've looked at (93-98)

You'll need are a bellhousing from a AX15 to 4.0L jeep engine combo in a 93-94 Grand or a 94-96 XJ (97-01 XJ's and Wranglers may work but i KNOW the noted will)
A crank sensor NAPA ech# CSS612
the most important part is that the bellhousing you use MUST use an external slave cylinder!
If you use other different years you may have to tinker with the crank sensor application

and of course you'll need an AX15 (hopefully with t-case) which they used from 89 to late 90 something in just about anything with a Jeep emblem - LOL

you can buy the flywheel & clutch new from NAPA for a 93-95 grand
nnc part# 50-1002 flywheel
&
nnc part# MU18901D for the clutch set (comes with throwout & pilot bearings)

you can buy the rubber part of the trans mount from NAPA for a 93-95 5 speed Grand,
you can buy the Clutch master and Slave as an assembly already bled out brand new from www.jeepshop.com
and
from Chrysler (same part # as Jeepshop.com I believe)
from NAPA you can only buy the master,
which sucks (they list it as a Clutch master assembly but all you get is a master & line for WAY too much money)

I think you can buy the metal part of the transmount assembly from Chrysler, and if not it would be easy to fab
(I'll take a pic of my girls factory 94' manual tranny bracket here eventually to post up)
I however used a 94' XJ AX15 tranny mount bracket, cut off the exhaust hanger part & bolted the 42re trans mount right to it, then bolted up the factory 42re crossmember which all fit together almost perfectly (the mount studs were a little short, but with plenty of thread engagement that I felt to be safe)

The only truly specific junkyard and very hard to find part you'll need is the ZJ specific Clutch and Brake pedals, however i have heard that it is possible to do some modifying of the XJ clutch pedal to get it to work in the ZJ (at least one person I've talked to was successfull doing that)
But it would be best (and not nearly as hard) to use the factory setup

I searched on car-part.com for any ZJ's with a clutch master cylinder in America and I called just started calling those places to see if they still had the stickshift Grand and wether they would strip and ship the pedals assemblys/brackets, and shift boot to me UPS cause i would prefer if this conversion appeared and operated like it would have stock

I contacted a Jeep specific junkyard in California www.jwjeep.com that sounded like they knew and understood exactly what i needed, they sent me the pedal assemblys with brackets, bolts and hardware
real good outfit to deal with and everything looked perfect

You will need to ground out the NSS (Neutral Safety Switch) otherwise it won't start. however by grounding the NSS you'll also turn off the cruise control.
Ultimately you'll have to either make a clutch safety switch using the NSS wire (which my girls factory 94' manual did not even have),
wire in a momentary switch (which would suck if you had to crank it while on a trail obstical)
or do what i did, leave the NSS wire taped up & ungrounded, locate the ground terminal of the starter relay, then cut that wire to reroute it to a ground source.

If you care you can also pick through the wiring on the 4x4 indicator switch to get the control center showing what 4x4 function your in again, but it won't hurt anything if you don't (there will be no lights flashing or warning messages if you never hook it up again)

I'll most likely just tuck all of the other wires up that go to the TCU, but wrap them with that heat protectant stuff first.

I also scrapped the trans control module that was mounted where the clutch master had to go, it is of no use once the auto trans is eliminated

T-case's;
--------------------------------------------------------------------------------------

I simply purchased a 93' YJ 231 with the short input & after verifying it would engage the tranny seal fully (but barely) i bolted it up and ran with it without any problems or leakage.

But Your basic choices are (for an offroader anyway);
the NP242 or NP231

The 242 out of my 42RE equipped 95' Grand has what i believe to be the 23 spline med. length input gear and it will slide right onto and line up with my AX15 output shaft and the 6 bolt holes will also line right up
it is also long enough to engage the trans seal with plenty to spare so i feel it would not leak
BUT they stop about 5/8 of an inch from mating together completely due to an internal "bearing" surface inside the t-case input gear

after examining the 42RE and the AX15 trannys
I can see that the seals are the same depth into the housings (give or take 1/8") and the shafts both stuck out approx' 1/2"

the difference lie's in the fact that the end of the 42RE output shaft is machined to a bearing style surface to ride inside that "collar" previously mentioned

that is the reason for the t-case input gear "collar" setup, it is apparently used to help keep the shafts running straight and true on at least the 42RE in some years

So the options are:
-machine down the end of the AX15 output to match the 42RE output's bearing surface
-cut approx 3/4" off the AX15 output shaft
-get a T-case for an AX15 tranny (i have heard there was an output shaft length change during the years, don't know for sure yet though)
-machine out the internal collar
-swap in a new input gear
(this can be very tricky see link below for more info
http://www.novak-adapt.com/knowledge/np231.htm)

using a 3/4 spacer will NOT work as an on road solution because you will pull the input gear out of the transmission seal and it will leak fluid through the weep hole


Driveshafts;
--------------------------------------------------------------------------------------
Rear drive shaft will end up about 3" too short (make your own measurements, this is approx.)
front shaft will be about the same too long, and should bolt up no matter which case you use
(the YJ 231 used a standard 2 joint shaft with u bolts , but the CV assembly used the same size joint so the bolts went right through the u bolt holes and everything lined up perfectly)

I ended up using a 76' & older chevy p/u front driveshaft which was exactly the right length & very beefy
(couldn't tell you which application but theres only 2, most likely it was a TH350 np203 combo but be sure you check for yourself)

& i simply had a the rear shaft re-tubed to length with heavier tubing for resistance to rocks & ETC. (figured while i was building one myswell beef it up)

I recomend ultimately using either a 2 joint (non-CV) front shaft or a HP30 front diff for vibration resistance without caster problems for any lifted Grand, but it will work fine with only mild vibrations going the route noted above)


Interior;
--------------------------------------------------------------------------------------

The XJ shifter lever will work fine, bends are decent & don't interfere with anything during use
A Hurst metric T-handle shifter fits very nicely after trimming about half the threads off the XJ lever

You can still buy the shifter boots (rubber lower & leather upper) & hardware through Chrysler
The sub-floor pan needs cut out where the factory already marked it, but i suggest buying the rubber shifter boot first because there is a very small margin of error available to get a leak free seal between these parts.

You only have two decent T-case shifter options available if you use a 231
-Find a Grand cherokee np231 shifter & bezel (good luck with that!)
-or do what i plan to do & simply modify a straight line Quadra-trac 249 shifter to shift the 231 completely ( i plan on still installing a 231 shifter bezel eventually when i find one, for now though the 249 bezel will be fine)

once all the interior mods are finished your factory console should mate right up with your new tranny as if it was always like that



I hope my research & experiances will help make this job much easier

Good luck with your awesome and rare conversion.
__________________
Showin' Dem' how she's dun'
At
www.blwa.org

DJJordache
12-28-2005, 11:04 AM
wow man nice writeup but some pics would be great! I always wanted a ZJ with a stick, but I have the 42re and a spare one also waiting in my garage with only 54k for my 4x4 swap:D

ILikeMud
01-11-2006, 12:58 AM
Good info.
I'm thinking I'll be doing this soon as my tranny is acting screwy.

KeepItCrunk
03-31-2006, 05:10 PM
I'm jsut about ready to start undergoing this process. I called this place yesterday about a bellhouseing and he said the part numbers for 93/94 xj, 94-96 xj and 94-03 wrnaglers are all the same. I was under the impression that in 99 they swapped to the NV3500, but that may just be me and they really did stop the ax-15 in 03. either way, the 94 bellhousing does match visually so that means you can say 94/95 yj's will work for 100% sure. TJ's unil they stopped using the ax-15 may work but im not positive right now.

gunthagunth
04-01-2006, 07:28 AM
i still need to find my transmission and bellhousing for my swap. i need to know exactly what to look for. i just dont wanna try and bolt the bellhousing up to find that it wont fit. i got my pedal assembly and shifter with boots tho.

ILikeMud
04-01-2006, 10:54 PM
My trans is from a 94 YJ, it's got an external slave.
Plus I've got the YJ 231 bolted on to it too.

Airmanwoody
04-04-2006, 12:50 PM
The 3550 uses the same bellhousing as the AX-15. That's why the numbers are the same. Just make sure to get an external slave, otherwise you'll hate maintenance on it.

KeepItCrunk
04-04-2006, 05:04 PM
Just got the pedal assy from JWjeeps in cali... LAST ONE!!! im so siked. im goin to measure my friends driveshafts in his 5 speed zj as soon as i get him that rear window from my parts rig. Then it'll be a gooooo.... so stoked, thats gonecheechin n everyone else for the help.

dunl
04-04-2006, 08:12 PM
I got a quote for these pedals today, so maybe they still have some....

gunthagunth
04-11-2006, 04:45 PM
just a question on the OBDII zj's that would attempt this. i just heard for the first time that the cps would not like the idea of running a stick in a ODBII computer. the OBDI systems dont mind the tranny swap and do it with no problems. i didnt know if anyone sucessfully did the swap on OBDII and had any tips to get around this. i was told to either convert the system over, which i wouldnt know where to start, or use a cps out of a 99xj 5spd due to the fact that the system is OBDII, but that method has not been confirmed to working. I saw the cps napa part number you named for the cps and im assuming that is for OBDI or maybe im confused and its a universal part.

DJJordache
04-11-2006, 05:18 PM
well the 97 XJ and 97 ZJ CPS have different numbers when looking at the Jeep part numbers but it doesn't show a difference between the AW4 and the AX15 on the XJ part list there is only 1 part number listed for the XJ 4.0L

gunthagunth
04-11-2006, 05:26 PM
:shake: I was hoping they would be different. so a OBDII computer in a xj must be different from a OBDI zj

KeepItCrunk
07-07-2006, 04:49 PM
The crankshaft number you gave, CSS612, have been changed to CSS613. If your lookin for a 99 5 speed xj css that part number and another will come up, however the other will not be the same connector as a zj, CSS613 will be. My swap is done... going to go see if that sensor will get her going. Now it turns over w/o spark, as somewhat expected... wireing time... hopefully not.

KeepItCrunk
07-07-2006, 06:06 PM
Well, CSS613 works. she started right up. WOOOOHOOOOOO im so amped right now... oh my god. 5 speed ZJ on an OBDII!!!! do my tcase linkage NSS button an reverse lights tomorrow and call it gooooood. thanks man, couldn't have done it without this write-up. this is an awesome and easy swap aside from what you may think. i thought i was in way over my head but now its done and working. mallcrawlin RULES!!!

ILikeMud
07-08-2006, 12:16 AM
Let me know what you do about reverse lights. That's one thing holding me back right now. That and buying the pedals and clutch master lol

gunthagunth
07-11-2006, 11:12 PM
thats awesome to hear about the obdii. i sold my pedals and shifter for 200 bucks. i got them for 30 so i cant complain. going level10 instead.

KeepItCrunk
08-12-2006, 01:08 PM
Just a follow up. Theres gonna be a thread about rebuilding an AX-15 in about a week beucase i jsut blew mine.... 150 dollar gamble, beat the bag outta it for a month tho, so im not gonna cry. Anyway, The mpg increase is actually amazing. I went on vacation last week, on the way there i was mad light footed, but i was really loaded down, and i averaged 18.3. Ont he way home i wanted to get home for warped tour really abd so i was lead footed and averaged about 75 or 80 all the way back, with the same ammount of stuff in the car... and got 17.9!!! just driving around like normal i get around 16 in the city, and hover above 20 on 40-50 mph roads. Thats ridiculous beucase with an auto and stock i was gettin 17.5ish and witht he lift n tires and an auto i was gettin 13.7!!!! I have tires that measure up to a true 31'' right now and 3.55 gears. im loving it and id recommend the swap to anyone, beucase it was way worth it.

gonecheenin
09-19-2006, 09:39 PM
I wrecked mine soon after the swap was done (dec. 05)
I've been parting it out ever since
(I'm keeping most of the hard to find conversion parts though in case the AW4 starts going out of my 93' street wheeler )




Reverse lights wire right into the AX15 reverse light switch
Its been awhile but if i recall the autos NSS had the reverse lights & NS all in one (3 wire plug)

I believe the NSS wire is the one thats black with a white tracer, i still have the ZJ carcass in my driveway & can check for you if you want


I'm real glad to hear that all my work helped you guys out with your rigs conversions. Makes the loss of mine a little less painfull too.


The OBDII conversion one, any check engine light from the tranny signals missing? Thats the only thing i could figure might be an issue, even if it was I'm sure a custom chip or something could be burnt to have the computer ignore the tranny signals




BTW: The fuel mileage has to be one of the best parts of the conversion!

Airmanwoody
09-30-2006, 02:24 AM
I've now driven my converted ZJ from AZ to AK and to MN in between. It got 5000 miles pulling a 3200 lb trailer during the trip and averaged 15 while pulling.

I was on 31's with 3.73's and was getting 18 in town and close to 20 on the highway. I'm not on 33's and 4.10's with a rear locker and get about 16 in town and 18 on the highway.

I love it and it saved me money in Dec and saves me money everday with the gas bill.

TN-95' ZJ
12-26-2006, 04:49 PM
Sorry to bring back an older thread. But my 42RE is screwed up. Took to dealership today and they brought up codes that show there is something wrong with the transmission and the actual wiring harness. They quoted $3000 for the rebuild and a new wiring harness but they would have to make a harness cause mopar doesn't have any listed. So my question is how much does the swap to the manual cost? Jeeps probably only worth $4000 in it's current condition, maybe less. Any help would be great.

Thanks

mudforblood
12-26-2006, 05:47 PM
I had a transmission shop tell me I needed a $3000 rebuild on my automatic before it was even pulled in to the shop:smt019 so I left.:butthead: I read somewhere about a plug coming loose in the pan, so I figured it couldnt hurt to check. Sure enough a plug was loose, plugged it back in and away I went.

I cant remember what it's called but it locks the torque converter up. Being unplugged it would lock the torque conv. and would make it bitch to stop. Just a thought.

I paid $300 for JY AX-15, $130 for new master and slave, and cant remember the rest. Overall it's alot less than $3000 (if you do it yourself) plus you dont have to worry about it leaving you stranded like when an auto. dies.

Airmanwoody
01-08-2007, 02:29 PM
Mine cost me close to $1100.

Here's a thread on it. I had another one that was better, but the pictures in it disappeared. (http://www.arcticoffroad.com/forum/showthread.php?t=286)

94 Grand
05-14-2008, 07:20 PM
I'm getting parts together for the swap. And the way I understand only the bellhousing has to be specific to the 94-96 XJ or 93 ZJ or 94 YJ with the external slave. Is this correct? And the AX15 and transfercase can be from pretty much any year? Thanks

SirTank
10-29-2012, 10:37 PM
Just a note i'll add here, i did this swap in my 98 ZJ but mine has the 5.2l V8 which is totally different then the 4.0 as far as matching up the bolt pattern.
if you are looking to do it for the 5.2 i got the transmission out of a Xj 91-99 and then a transmission bellhousing from a 94-98 dodge dakota sport with the 3.9l v6.
this engine has the same block design as the 5.2 but just has two cylinders cut off and the sport edition has the AX15 in it. so then you can pair up the v8 with
the AX15 and i have run mine wheeling for over a year without any problems.
Total cost was around $950 i did junkyard parts and all the labor myself.
one pitfall is you have to cut and re- wield all the exhaust being as the dodge bellhousing relocates the starter to the driver side.
threw in a 231 and away i went.

hansshanks
02-25-2016, 01:02 PM
reviving a old thread, SirTank, which flywheel/clutch combo did you use for your 5.2/AX15 swap. I am currently considering the same to my 94 zj




Just a note i'll add here, i did this swap in my 98 ZJ but mine has the 5.2l V8 which is totally different then the 4.0 as far as matching up the bolt pattern.
if you are looking to do it for the 5.2 i got the transmission out of a Xj 91-99 and then a transmission bellhousing from a 94-98 dodge dakota sport with the 3.9l v6.
this engine has the same block design as the 5.2 but just has two cylinders cut off and the sport edition has the AX15 in it. so then you can pair up the v8 with
the AX15 and i have run mine wheeling for over a year without any problems.
Total cost was around $950 i did junkyard parts and all the labor myself.
one pitfall is you have to cut and re- wield all the exhaust being as the dodge bellhousing relocates the starter to the driver side.
threw in a 231 and away i went.

StickShiftZJ
10-20-2016, 12:11 AM
I hope its ok to post this here, but it may help out anyone doing a stick shift conversion to a ZJ. I got a hold of a factory stick shift ZJ, pulled out the manual transmission parts, and I'm going to be reverse engineering them one by one. I finished with the clutch pedal bracket, which seemed like the biggest PITA since I hate working under dashboards. I copied the factory one, added a switch bracket for the NSS to be triggered by the pedal, and I had a few made. I've got a few extras, so I threw one on ebay in case anyone else would need it.

hansshanks
10-25-2016, 12:02 PM
could you pot a link to the ebay auction I cant seem to search and find it. Also could you post some pictures?


I hope its ok to post this here, but it may help out anyone doing a stick shift conversion to a ZJ. I got a hold of a factory stick shift ZJ, pulled out the manual transmission parts, and I'm going to be reverse engineering them one by one. I finished with the clutch pedal bracket, which seemed like the biggest PITA since I hate working under dashboards. I copied the factory one, added a switch bracket for the NSS to be triggered by the pedal, and I had a few made. I've got a few extras, so I threw one on ebay in case anyone else would need it.

StickShiftZJ
10-25-2016, 05:04 PM
I'm not able to post attachments, but I do have a pictures on my web site, stickshiftzj.com. Its a work in progress, I'm still adding info, but is has some of the basic swap info and pictures of the pedal bracket. You probably didn't find it on ebay because I sold the one on the listing early this morning and just relisted another. Its item #162254776813. This is my last one, but when this one sells I'll have another batch made. The laser cutting is pretty quick, but the CNC forming had a pretty good lead time, the first batch took me three weeks.

Yjsaabman717
03-19-2017, 08:20 AM
Damn...you couldn't have posted this before I rebuilt my auto? Lol!

Yjsaabman717
08-12-2019, 01:04 PM
Bumping this back up as I have pretty much everything to swap my 94.

Going to throw in this note about using a YJ trans: the t-case clocking is different. I found this out when installing an XJ AX15 into my YJ many years ago, the t-case hit the floor in the YJ. The trans does have enough material for both positions/clockings. I ended up just making a template and drilling mine to fit the YJ. I have an XJ trans for my swap in the ZJ.

Sent from my SAMSUNG-SM-G930A using Tapatalk