• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Transfer case spline count info wanted.

lunghd

NAXJA Forum User
Hey all - Looking for New Process transfer case information.

Transfer Case spline count project

Link goes to my site & page there is pretty self explanitory but briefly what I'm looking for is: the tag information from any New Process transfer case along with the 'SPLINE COUNT' for that case.

Knowing what part number range covers what spline count would be handy info to have when scavenging among pre-pulled tranny/transfer cases especially for those w/ transition year XJ's when Renix phased out & HO motors kicked in and transfer case splines changed from 21 to 23 spline. ( So far as I know; the change follows the closed / open cooling - Renix / HO motors.)

This information will assist determining what spline count a given transfer case will have WITHOUT splitting the transfer case from the transmission to physically count the splines. This information may also assist you in finding a transfer case with the correct spline count when swapping to another where the spline count may be different than the original case.

Basically, check the xfer case tag, post or email the info WITH THE SPLINE COUNT with any other info ya can give and I'll keep compiling it.

Thanks!
:anon:
Transfer Case spline count project
 
NP231

"There are versions of this chain driven transfer case that take 21 and 23 spline input shafts. The 23 spline version is used behind the AX-15 and the 21 spline is used behind the AX-5 and the BA 10/5. The output for the front driveshaft is on the drivers side. Low range is 2.72 and high is 1.00."

I think the AW-4 mated to the NP231 was always a 23 spline. I was under the impression that the tranny determined the spline count AND the shaft length... I think the best way to avoid the swapping of parts is to just check that your tranny and the donor Jeep's tranny are the same. I could be wrong though.

http://www.jeeptech.com/xfer/np231.html
 
If only it were that simple... Yup, I've seen that site before. It was linked in a similar thread on JU but they no longer archive their old threads so all that info is now gone.

* - Early XJ's (Renix / Non-HO) ***SHOULD*** have 21 spline outputs on the tranny & inputs on the xfer cases regardless of auto / manual.
* - HO XJ's ***SHOULD*** have 23 splines regardless of auto / manual.
* - If the tranny/transfer case is still in the XJ: - the 21 / 23 spline "split" ***SHOULD*** follow the open / closed cooling system change-over.

Problem is when a boneyard pulls the engines & trannies and places them up on a rack... how do ya know then? Or if they even came out of an XJ? The whole point is to be able to read the tag on the Xfer case & know the spline count without having to split them apart.

Ex. - My 1990 AW4 / 231 has 21 splines but my Dana 300 has 23 splines. To install my D300 I need a later AW4 transmission with 23 splines. If the boneyard didn't mark the year model etc on the transmission... I could lay my tranny / xfer case right beside theirs and there'd be no way to know if the other was same spline count... or different... without splitting them apart (which the boneyard may not be willing to do). It also helps if ya gotta id what ya got inside a running vehicle before ya go to the boneyard.

The sole purpose of this information is to decode the part number 'range' of 21 & 23 spline xfer cases so ya can read the tag & know whatcha got without splitting the case from the tranny.
 
Back
Top