90 XJ t-case input splines

[1990JEEPXJ]

hmmm. i typed in the part number from my transfer case and more online investigation lead me to this...

http://www.lunghd.com/Tech_Articles/Transmission_and_Transfer_Case/Transfer_Case_ID_Project.htm

but there is a disclaimer that states this is contributed info which makes me think of a wikipedia type deal. but the exact number from my transfer case is there and
specifically says 21 spline.

edit: found this as well
http://www.jeepsunlimited.com/forums/showthread.php?t=205654

it appears that 21 spline it is...

 

[kastein]

Fun.

So who are you gonna believe? My first post (21 spline) or my second (23 spline)? lunghd (21 spline) or the jeep parts catalog (23 spline)?

I honestly can't answer this question definitively... I would pull the case and count.

 

[1990JEEPXJ]

haha exactly. it seems like a wild goose chase. well i will be pulling it here in the next few days, i will definitely report back on this one. im kind of thinking rebuild at this point. would make me feel better knowing it has fresh new parts and i dont have to deal with re doing my SYE. so onto my next question, what rebuild kit is recommended? i definitely need a new chain so which is best?

 

[5-90]

If you can see the 8 digit Chrysler part number on either the transmission or the transfer case, and the serial number off the transmission, I can tell you for sure.

Transmissions serial number 131163 and earlier are 21 spline (in XJs and MJs) while transmissions serial number 131001 and earlier are 21 spline in YJs. 131164 and later (XJs/MJs) or 131002 and later (YJs) are 23 spline.

Looking at the page for the transfer case year splits makes my head explode. There are different listings for various combinations depending on XJ/MJ/YJ, 4cyl vs 6cyl, 5spd vs auto vs peugeot, 87-89 vs 90, 231 vs 242, with different exact build date splits for each. It is truly mindbending and there are something like 28 listings, some with different and conflicting/duplicate part numbers. I'm not even going to try and interpret it because I know I'll get it wrong. The serial number is probably the most reliable "book" method of telling you which you have, short of going back in time and entering your VIN into AMC's computer database, but the one true way of really telling for sure is to pull the damn thing apart and count.

Built in may 90 *looks* like it might actually be 23 spline but I'm honestly not sure. Most of the build date splits are on various days in october and november of '88 (wtf?) and '89. The real problem is that model years and year of manufacture are nowhere near hard and fast and overlap in strange ways.

If you can get me copies of your sources, I'd be happy to work on the bar charts - it's right in line with what I'm doing for Swappology anyhow.

The late-year 88 splits (mostly AUG88, but some afterwards as well...) are basically because that's when ChryCo took over production from AMC, after purchasing (and then dismantling) AMC.

Why do you think the J-series fell over after MY1988? They didn't want it competing with the D-series and W-series pickups of their own...

 

[kastein]

I'm fairly certain I sent you info on some of my sources - they're the only hardcopy I have, the rest of my info is gleaned from here.

 

[1990JEEPXJ]

well i decided on the rebuild kit. got a timken bearing and seal kit. part number TCRK-242. and a cloyes replacement chain off ebay. im also getting a new filter, misc o-rings, and all of the shift fork pads from morris 4x4. ill report back in a few days with the spline count.

 

[1990JEEPXJ]

ok so it is confirmed. 21 spline. just pulled the t-case for rebuild.

 

[cruiser54]

ok so it is confirmed. 21 spline. just pulled the t-case for rebuild.

Glad to hear that. Encourages me to swap the NP242 I've got in the shed for the NP231 in my 90 MJ.

 

[5-90]

I'm fairly certain I sent you info on some of my sources - they're the only hardcopy I have, the rest of my info is gleaned from here.

I'll have to pillage around and see if I can find them. I don't suppose you have the ability to scan what you have in hardcopy, do you? Pweez?