BigRed93xj

This is possible right? I've heard of people swapping to a NP 242.... I have the 5.2 v8 if that matters. From what I've read I just need to find a Transfer Case with a 23 spline input shaft. However Im hung up on the length of the input shaft...... Does it have to be 2 1/8"??? Please all the info I will need is welcomed. I basically want to make sure I know how to identify the right tansfer case when I do the swap because I know there are different input shaft sizes...... Thanks guys.

ol"blue

Don't know about that swap, but I've read that the 249 is a better swap. Here's a write-up on that swap if you're interested. > http://www.kevinsoffroad.com/techart...-242_swap.html

BigRed93xj

yea i've read that write up. Im wondering if a np 231 is possilbe which im sure it is. I see more people swapping form a np 249 to a np 242. Whats the benifits of doing this?

ol"blue

You get the option of 2WD. With the 249 you don't.

BigRed93xj

which is the whole reason why im doing the swap, plus the VC in the 249 is slowly but surly going out. I found a NP 231 in my area for $200. But Im not sure if thats too much. The pick n pull in my area is RIDICULOUSLY EXPENSIVE. They wanted $300 plus tax for a dana 30.

BigRed93xj

I guess what Im hung up on is that I see all these people swapping from a np249 to the np242, why not a np231. I know the np242 has more options like part time/ full time 4wd. But there's way more aftermarket support for a np231.....

ol"blue

I don't have an opinion/answer for that.

OverlandZJ

Lots of guys swap in 231's to their ZJ... matter of fact they were available in ZJ's.

It comes down to which is right for your application, swap in what works for ya.

snowboard3r411

so is there any write ups out there on a np231 swap??? and also i have a 1998 5.9l so do i have the 249 then?>>?

ol"blue

The 5.9L's didn't offer the option of 2WD because the t-case wouldn't hold up.

x91j

i just did the 249 to 242 swap. i just grabbed a 242 out of a wrecked zj at the jy and swapped it right in

BigRed93xj

yea, the local junk yard has a flat rate of $190 for any t-case..... I found a freaking crap load of them yesterday over there. But they all look beat up and torn apart.... argh I guess Im just going to have to keep an eye out.

CigarXO

BigRed -
Did you ever get your questions answered on this swap?
I'm considering the same. '98 zj 5.9r. Found a 93 zj 4.0 with a 231. but, recent readings of gear cut... has me unsure. Cannot find much info on the 231 swap, though you see guys with them in their ZJs.
Any info would help.
thx
CigarXO

ol"blue

Welcome to CF. You don't want the '93 t-case. Read this: http://www.kevinsoffroad.com/techart...1caseswap.html
And this from Pirate4X4:
02-16-2008, 08:11 PM #3 jfowlzj95
Registered User

Join Date: Sep 2006
Member # 78761
Location: College Station/Austin, Texas
Posts: 46


I did the swap last March, it's fairly simple once you get into it. I had to swap my input shafts, got my 231 for a 96 XJ. But yeah getting the linkage right took some time.

Here's some measurements that'll help you find out if you're gonna have to swap inputs or not, chances are you probably will need to though.

Originally Posted by DJJordache
this should help ya... the only one I don't know about are the ones that came with the AX15.....
ZJ 93-93.3 4.0L aw4 = short
ZJ 93-95 4.0L = medium with internal collar
ZJ 96-98 4.0L = medium without internal collar
ZJ 93-95 v8 = long
ZJ 96-98 v8 (both) = medium without internal collar
short = .750" exposed
medium = .840" exposed
long = 1.55" exposed
__________________
Ouch

blackjack12982

What? You've given out some pretty terrible information in this thread...All V8 ZJ's came with the 249 TC stock, the 249 was considered the strongest case, with 231 a very close second, and the 242 a distant third. Plenty of 5.9's have 231's swapped without magically blowing them up...

This is the writeup that I used, there's plenty more writeup's out there.
http://www.jeepforum.com/forum/f13/t...-np242-685644/

The thread I linked above addresses that issue. The gear cut change happened in the middle of the 1994 model year.

Quoted from the thread-
"It's best to go by the build date on the transfer case, not the year of the Jeep when determining the gear pitch. Rule of thumb is cases with a build date of pre 94.5 will have the old style gear cut, and cases with a build date of post 94.5 will have the new style gear cut.

The correct way to read the date is just how it looks. Month, day, year. So if your case says 8 15 92 1, That would be August 15th, 1992. Most manufacturers aren't this specific on the manufacturing date which would lead you to believe "1" would be January, 1992, however the last number is insignificant.

My personal experience is that a 249 with a build date of 7/94 still used the old style gear cut."

My own experience was the same, my 94 ZJ had a build date of 7/94 and used the older style gear cut. I swapped in a 231 out of a YJ, and swapped the input gear. That was done in very early 2008, and I've had zero problems from the 231 since.