Hey guys, I have a quick question. I own an '87 Cherokee with an automatic transmission. I have the NP242 transfer case. I have heard some conflicting information about the case, mainly either it sucks or its great.

I would like to know if the NP242 transfer case is ok for my needs or if I need to start looking into a swap to a NP231. Also, I am lifting my XJ so I will need a SYE which is specific to the transfer case and would like to decide if I want to get the SYE for the 242 or swap everything out.

I will have the XJ lifted 4.5 and running 31's. It will be mainly an off-road rig, but also a vehicle that I will use to travel in to find some good 4 wheeling places. I live in New Mexico and the weather isn't inclement, so the full time 4wd isn't necessary. I will be taking the XJ to the mountains, into mud, lots of sand, but I am not big on rock crawling. I just want something to go exploring in and I don't have to worry about breaking stuff on it. Eventually I will be upgrading a lot on it, but I want to see what the best option is for me right now.

I have also heard the the transfer case isn't as much of a problem as is the axle type? I'm in a bit of a conundrum. Any help is appreciated. Thanks!

 

First off the 242 is a transfer case not a differential. Differentials are in your axles although the 242 does have something simular to a differential that it uses in it's AWD mode (full time). The case isn't all that bad but if you plan to use a SYE your only option is a hack and tap and there are no lower gear options. Not sure what rear axle you have but that is a bigger concern than the t-case. With 31s the axle isn't that big of an issue but if you plan to go bigger replace it. I wheel with several people with the 242 and they work fine just don't use the full time mode off road because it's worthless.

 

The NP242 is a transfer case and not a differential. It's trade name is Select Trac, and it's a great transfer case for all weather driving on road, but it's been known to be a bit weaker than the NP231 (or the Command Trac) and therefore people do prefer the latter. It's an easy enough swap, but I'd drive it until it broke personally.

 

Haha, sorry. I'm thinking differential because I'm currently sitting in my statistics class and I have some vocabulary flying around. I'm just bored and thinking about my Jeep.
I actually have a guy who can make me an entire drive shaft so I can avoid the hack and tap method. Never heard of that option before.
I have the dumb Dana 35 rear axle.
And on second thought, I have to check and see if I have two different 4wd high modes (both the full time and then the 4wd locked). I might just be jumping the gun. Again, I'm just bored and thinking waaayyyyy too much about my Jeep lol. Is there anyway I could have a NP231 in an 87? I am not sure if it was swapped out. Man I should really get my crap straight before I post huh? lol

 

If your XJ will be primarily for wheeling then I would maybe think about doing a tcase swap to the 231 mainly because you have way more options when it comes to doing a sye, especially the hd sye. The clearance is better with a 231, and they are readily available should it need to be rebuilt, replaced etc. The 231 handles more torque than the 242...I'm not hating on the 242 by any means, I have one in my Jeep, but from what you described, I think a 231 swap is the way to go IMO.

 

Are you saying you're not sure if you have the NP242? If so, it's unlikely that you do. Most XJs from any year have the NP231. Probably to the tune of 90% or better.

 

Yeah, I jumped the gun big time with the transfer case. I was just worried because everything so far on this Jeep has not been the normal XJ fare. But, with the good help of a fellow XJ owner and good friend of mine, I discovered that I do indeed have the 231 transfer case. This means I can stop worrying about swaps, or specially made parts. I can just buy my stuff and go wheeling and finally get the Jeep in some good ol' Earth.

Thanks for the help guys. And I shall definitely get my story right next time before I post. And I will stop posting while I'm in class, with my eyes glazed over.

 

Only bad thing about having the 231 is that it means you have a CAD axle.

 

If you don't mind me asking...what is a CAD axle?

 

Central Axle Disconnect. The passenger side axle is a two piece design instead of one. When the t-case is put in 4wd a vacuum motor moves a fork that slides a collar across the two shafts to make them work as one. The vacuum motors tend to be problematic and if a line breaks, rots etc your front axle won't engage. You can bypass this with a cable kit, permanently connecting the two shafts or swapping in a later model one piece shaft. This was done to increase gas mileage but later found to not make any difference in mileage.

 

Yeah, that's the only thing I could think of. It's only on the earlier model front ends though correct?