DualSportDad

i have a 97 xj with a aw4 that just crapped out last night. i need to have this swap done before next weekend so i'm looking to order the parts now.

i have a 242 transfer case and a 8.25 rear.

what parts do i need to order and from what vehicle? i have been searching and am reading that different transmissions have different output splines and they **** the t case at different angles.

i'm a little confused and need to make sure i have everthing i need and right the first time.

thanks for any info.

JeepCoMJ

requires replacing complete engine bay wiring harness, engine computer, transmission harness, front AND rear driveshafts, shift linkages (including body side bracket, which requires removing lower interior trim, seats, and carpet), complete pedal assembly, transmission tunnel block off plate, flywheel, inspection cover/shield, obviously the transmission as well, and i'm sure I'm forgetting something else.


basically, to do it on a '97+, you need a complete parts vehicle, and you have to gut both vehicles. there is no "ordering parts" for it. if you don't have all of these parts from a parts vehicle, there is no feasible means to accomplish the swap.

IF you can get all of the part numbers for all of these parts from the dealership (which WILL be the only place you can get them from, if at all), you will be spending over $2500.

DualSportDad

can't i just jump the nss and not have to swap the wiring harness etc?

i was thinking parts would be: pedal assembly,clutch master and slave, flywheel and bolts, clutch assmbly, possibly driveshafts (which sucks cause i just put a new one in the front), transmission, t-case linkage, trans mount.

i dont care how clean the install is so trim pieces don't matter.

e30

ive been a part of 2 bmw auto to manual swaps and bypassing the nss is prob your best solution....i see no problem doing that...and no reason it shouldnt work

JeepCoMJ

you can bypass the NSS, but your reverse lights will not work.

also, IIRC, there are some engine computer pins missing in the auto harness to the 5 speed ECU. you can't do the swap without putting the 5 speed ECU in it, as it will throw check engine codes.

you'll also have to remove and jumper several pins on the transmission computer connector, IIRC.

doing a clean swap is really the only good way to do it. any other way, it probably will have little quirks that will be hard to track down.

my old '97 was 4.0/auto, the motor was bad, I bought a parts '98 4.0/5 speed, and decided I wanted a 5 speed. did the mechanicals first, only to realize how much other work had to be done to make it actually function appropriately.

DualSportDad

i think i'm just going to put another auto in it.

94XJCherokee

I did a manual swap in my 93. only wiring i had to do was bypass the nss. Never got a check engine light either

DualSportDad

i have been looking and i can't figure out how many splines a np242 t-case has. i'm assuming that a ax-15 has a 29 spline output shaft so the np242 probably has 23? i forget but i know there are two different splines numbers for the np231 23 and i think 29? i have seen in my searches the np231 used on a uto and stick box trans xj's but the np242 only on the auto's? is this correct? if so i'm going to need a t-case as well.

i have to do something tomorrow, if i can have this all figured out by tomorrow afternoon i'll call the local junkyard and get the trans, t-case and pedals coming and then call the local parts store and get the rest coming and hopefully have the swap done by thursday.

ps i don't care about check engine lights, i'll just pull the bulb and scan the thing at every oil change to make sure there aren't any new codes in there that might need to be attended to.

JeepCoMJ

you're in over your head. 29 spline output?

....21 or 23, with long or short. the ax15 is 23 spline output, the np242 is 23 spline if mid 1991 or newer, 21 spline if older.


if you're doing the install, you NEED to pull the parts yourself.

and the engine light actually does matter. it does matter obviously for you to pass emissions, if you have them, but also because an engine throwing a transmission code will read that there are issues with the throttle position sensor. if that happens, it will run rich. if that happens, it will either keep wrecking 02 sensors, or keep clogging catalytic converters.

JeepCoMJ

yeah. you did a conversion on a non-OBD2 system. it's non-integral...meaning the ECU and TCU run seperately of each other, with the transmission kickdown cable being the only thing that tells the TCU what the engine is doing, allowing for proper shifting.

96 and newer are integral....the engine computer ultimately controls everything, from what the sensors do, to what the gauge cluster reads, to what the auto trans does. there is still a kick-down cable, but it's not nearly as involved in the operating process as it is in 95 and older systems.


this swap WILL cause a check engine light on an auto wiring harness, and it WILL cause running issues. take that from someone who has done this exact swap before, and who knows the ins and outs of 97-01 cherokees.

DualSportDad

is there not a trans controller still on this vechicle? i don't think the pcm is a ngc controller is it? what if i got a manual pcm and ran my own wires that are different from the manual pcm? i figure only a few pins could be differnt.

JeepCoMJ

you honestly don't seem to have enough knowledge base on this swap to accomplish that.

not that I do, either...I wouldn't attempt adding in the wires, personally. I don't have unlimited access to alldata, and while I throughly enjoy wiring, I'm content to just do it right.

there is still a trans controller on this vehicle. located above the gas pedal on a bracket mounted to the firewall. however, the auto ECU communicates with this TCU. because of the newer electronics system, this is just simply not a feasible solution.


plus, if you have to buy a master or slave on a 97+ xj, you have to buy BOTH...and they're over $300 for the pair. they come as a bled and plumbed unit.

this is an expensive swap if you don't have the donor vehicle. you will want to pull the parts from said vehicle yourself, so that you know where everything goes...and doing it the way you want to do, you surely will not accomplish it in under a week, if you have a job to do as well.

I'm a mechanic for a living, btw. my professional opinion...buy another automatic for it. if you weren't so far away, I'd sell you a 90,000 mile one for $50 to get it the hell out of my garage.

DualSportDad

unless i'm reading these wiring diagrams wrong i see no reason why the trans controller would have any effect on how the engine runs. the trans controller gets it's message from the TPS sent directly to it and the info is not shared through the BUS messages.

i am also a tech for a living....at a Chrysler, Jeep, Dodge dealership and i do electrical repairs as 75% of the work that i do. i have been Master certified for 10 years in electrical with Chrysler.

i don't work on many jeeps tho, mainly just Chryslers.

if i get the newer ax-15 with a external slave setup the pieces come separate don't they? i'm not too worried about what the piddly stuff costs as i get most of that very cheap. the driveshafts, trans, and pedals though will have to come from a junkyard most likely.

swapping the pins over and running my own wires will be a piece of cake for me if anything is needed. probably at worst i will have to get a pcm.

JeepCoMJ

see, perhaps you should give a background of what you have at your disposal to get things done.

I took you for someone who probably shouldn't attempt this swap because i don't know a single person who has ever thought any xj had a 29 spline transfercase, and the ways in which you deliver your questions signal to me that you didn't have much technical advantage on this project.


that said, from what I am aware, the trans computer will signal the ECU if not functioning properly (i.e. no trans), and the ECU will put itself into warm-up mode.


As I had said, I have done this swap on a '97 to a '98 system. using the auto wiring, the cherokee simply would not stay running, with neutral safety switch pins B and C connected to each other, effectively bypassing the NSS.


as far as parts availability seperate, no. the master and slave are not available seperate, from what 7 different parts stores and 4 different dealerships have told me. if you find out otherwise, let me know so that I can go raise hell with the dealerships.


if you want to mess with the wiring, fine. but you will need the 5 speed ECU for sure, you will need to delete the TCU, and bypass the NSS. there are dimples for the holes to drill on the firewall for the clutch master, and you will need the complete aluminum pedal assembly bracket with pedals etc. in order to get this swap done.

good luck, but I still advise putting an auto trans in it and calling it done.

Bustedknuckle

Then you're going to be receiving alot of PM's from me soon. Got 2 dirty 30's we're swapping in the next few months.

And +1 to keeping it Auto. The AW4 is damn near bullet proof, R&R and life will be good. Doing a swap, potentially getting overwhelmed & discouraged and annoyed, leads to giving up and selling the rig.