Hi guys,
So, I just bought myself a 92 Cherokee 2dr 4x4. I had the universal joints in the rear drive shaft replaced over the weekend, and my mechanic found that there is a giant rip in the transfer case (which is a NP231 in an automatic tran). *sighs*

My question is...what year models of Cherokees can I pull a transfer case out of to be compatible?

And also, how much does a tcase usually run for one of these vehicles? Junkyard or remaufactured, or what-have-you...

 

Never ran into a problem with a t case swap, but some are vacuum shift, so there may be some mods needed there, otherwise I'm pretty sure they stayed the same and will bolt right up. Around here JY gets $75 or so, depending on the yard.

 

As far as I know you would have to get a 231 from another rig with an auto, the splines are different between the auto and manual. And they are most likely the same from 87-01. You might be able to use one from a wrangler too

 

91 and older have vacuum lines for the vac disconnect front axle. You will want to find one from a 92-up.

 

Thanks for the quick replies guys! Usually when I post to forums it can be days or even weeks before anyone answers me :P

So, basically though, any 231 from an automatic XJ 92-01 will be my golden ticket? Does the new one have to come out of a 4x4 as well? (yeah I don't know anything about cars much..thats why I bought this jeep..to learn :P)

 

Well considering 2 wheel drive Jeeps do not have transfer cases, then yes it has to come from a 4x4.

 

haha yeah I guess I should have realized that...I have blonde moments sometimes XD

Thanks though!

 

The answer you have gotten are partially right. Stay away from 91 and older t-cases, unless yo uknow the spline count. It is possible to have a 23 spline case in a 89/90, but more then likely it will be a 21 spline.

After 96 they cahnged the out put shaft design on the t-case. So try and get one from a 92-96 xj. Wranglers have a different clocking on the t-case. IT is rotated to be flatter. If you use this kind of t-case you will need to use a different lower t-case shifter linkage.

 

x2 stick to t-cases from 92-95....then make sure the t-case you buy has the same Speedometer cable setup as yours (cable or electric)

 

Year of t-case does not mater if it is older than '97.

In '97 they made a spline pitch change in the case.

Reason year or spline count for that mater isn't a issue is this.

ALL 231, 242 and 249 T-case input shafts are swappable.

So split the new case and your old one and swap the old ones input shaft in. Very simple takes about 20 mins to do..

 

you dont want a 249, it is what they used in the grand cherokees and do not have a full lock up mode, not even in 4lo. any transfercase 88 (this is when they introduced the np231) -1999 will work from an auto cause they are all 23 spline, the manual version from 88-91 have the 21 spline count. you can get a 242 but it has a weak diff inside and is prone to breakage like the 249. 231 is the best one out there for you unless you can get your hands on a 241 which came in much later model wranglers. they have a 4:1 low range vs teh 2.71:1 range in the 231 which is pretty darn good itself.

 

Ok...

The 1992 should be a 23-spline input either way, so that solves that little problem.

The disconnect axle was discontinued sometime around 1992 as well. Check the passenger side (long) tube of your front axle for a vacuum disconnect actuator - if you have it, it's mounted with four screws on the backside of the axle tube. No actuator = no CAD and therefore no vacuum worries (the 4WD lamp will be actuated by a switch in the tcase itself.)

The only variable really then becomes the "stick-out" on the input gear - measure that and note it. Mounting stud patterns are all the same, and the "clocking" of the transfer case is handled by the adapter housing on the transmission (TJs and YJs have the transfer case 'clocked flatter' to the underbody to keep it from hanging up on anything. The XJ would need to have the transmission tunnel modified to clear use with a TJ/YJ transfer case adapter housing.)

Possible donors?
Check S-Series Chevvy trucks & SUVs (NP231C,) as well as the K5 Blazer, and K10 Pickup/Suburban (NP231C - the chain is slightly wider. Make sure the case is the same length as well - front mounting surface to tailcone end.)
Light Dodge (W100, Dakota, some BR15004WD) might have the NP231D - same deal as the NP231C. Same notes.
I do not think Ford used the NP231 - they tended to favour Borg-Warner cases (13-xx series.)
And Jeep - XJ/MJ/YJ/TJ and some ZJ - and don't neglect the later CJ (say, 1975-up.) NP231AMC/NP231J

I suggest you take the slip yoke with you when you go - make sure the spline count on the output is the same (I believe it is, but I wouldn't swear to it in court. Easy enough to check - just slip your output yoke in and see if it will seat fully in the case.) If you can get your paws on the NP231C or NP231D (or even the NP231HD or NP231DHD - both found in later Dodge full-size!) you'll also net an upgrade.

Note that all New Process/New Venture/New Venture Gear transfer case mounting patterns are identical to the late Dana 300, as used in the CJ. So, if you can score a Dana 300 and are willing to do some work, that is also an option for you.

If you can't find a 23-spline case (which would be odd...) you can get a 21-spline and note the donor vehicle, then call Novak Conversions. They can supply input gears for most common transfer cases without too much trouble.

 

I'm not saying that's what he wants I'm saying ALL those input shafts are 100% swap able. You can make any of those t-cases swap with each other or swap there inputs..

 

To me it seems this this guy is paying a mech, or has lil knowledge of the jeep xj. (not bagging on you dude). SO why Not go to a j-yard and find the correct t-case to swap in, and not worry about swapping inputs. Now all that inof posted about the chevy and dodge t-cases is great info, if he has the knowldege to do that kind of stuff, as is the info about swapping inputs, but I dont think that was the info he was trying to get.

 

5-90, so its possible that a t-case from a 86 Suburban 1/2 ton will fit an 88 Cherokee?
I know its chain drive case, not sure on the model tho.
Thanks