: 231 question for the tech guys


Keith Strong
09-11-2001, 08:57 AM
Does anyone know what the input shaft length is for a 23 spline 231 out of a 95 YJ. It came from behind an AX15 <IMG SRC="smilies/confused.gif" border="0">

DUG
09-11-2001, 10:31 AM
I think it couls be either one. As far as I know there is no specific cut off for the input shaft length.

If you are ordering adapters order what you think you have and if you have to you can switch input gears.

Keith Strong
09-11-2001, 10:53 AM
I am asking for a friend...My understanding is he is swapping a 249 for a 231 and wants to make sure the 231 will fit.

DUG
09-11-2001, 11:19 AM
It really depends. In fact the 231 could even have a 21 spline and the 249 a 23 spline depnding on the build date and aplication. If he needs to he can switch the input gerar from the 231 to the 249 if he needs to. However, this may not be possible as some time in the 90's they switched the pitch of the gears on the 231.

Keith Strong
09-11-2001, 11:31 AM
The 231 definitely is 23 spline

Charly
09-12-2001, 05:34 AM
Keith,

According to AA's buyer's guide, the AX-15 will normally have a LONG 23 spline output shaft. So, I believe that, the 23 spline input for the 231 would be the shorter of the two available. The pics in the guide show the input for the 231 (for the long tranny output-- AX-15) to be the shorter of the two.

Actually, I'd suggest calling AA 800-350-2223 for more details. A guy named Vic there has been very helpful to me in the past.

Charly

DE Jeeper
09-12-2001, 12:52 PM
The NP231 attached to an AX-15 is the shorter of the 2 input shafts. I am 100% sure of this, the 231's attached to the autos are longer by about an inch. I have aslo learned of an additional difference between some of the newer cases. Apperenty, there are some double bearing input shafts that can not be used with the single bearing cases. I would say if they are both late model cases there is a good chance it will work, but I think you need to pull them apart to be sure.

MoabZJ
09-13-2001, 09:18 AM
After you swap the input shaft, do you have to 'time' the planetaries or do any other special setup adjustments so that the case doesn't break or wear unevenly?

Cody

CannonBall
09-13-2001, 01:51 PM
My 95 5.2 ZJ had the LONG input shaft about 2 1/4 inches. Changing them is a bitch.
-Nate

P&T Jeeps
09-13-2001, 07:23 PM
How important is it to actually match the right length output w/ input shaft length?

If the short shaft is adequate, why do you need the long shaft?

Littlex
09-13-2001, 08:12 PM
From seal surface out it is 3/4" on my old 231 from my 94 yj.

Littlex
09-13-2001, 08:12 PM
From seal surface out it is 3/4" on my old 231 from my 94 yj.

cbassett
09-13-2001, 11:37 PM
Originally posted by P&T jeeps:
<STRONG>How important is it to actually match the right length output w/ input shaft length?

If the short shaft is adequate, why do you need the long shaft?</STRONG>


If your setup uses the long shaft, using the short shaft will not provide a sufficient seal and you'll spew fluid.

MoabZJ
09-14-2001, 12:23 AM
Mine measures 1 5/8" and I know there is a longer one. Why do ZJ's have to be so damn difficult. <IMG SRC="smilies/mad.gif" border="0">

I guess I'm just screwed until I find someone that knows how to swap shafts. Everyone local here seems afraid of trying to do it.

Cody