Some 93 ZJ's had 231's (VERY rare)
93-98 4.0L have 242's
93-98 5.2L have 249's
98 5.9L have 249's

Most people that swap out their 249's have done so for 242's if they want to keep the all wheel drive option, if you don't really care then you can just go with the 231 as those are easier to find. Quick word of advice on doing t-case swaps, as it is not as straight forward as it might seem. Jeep's t-cases (249's, 242's & 231's) come with a variety of input shaft lenths (1.55", 0.84" & 0.75" IIRC) and you have to match up what your case is to the new case you're getting, the only thing is that there is really no way to tell how long of an input shaft is on your t-case until you remove it and measure. If you're handy you can just tear apart both cases and remove the input shaft from your original case and put it in your new case if the sizes don't match up and you're good to go. There doesn't seem to be any rhyme or reason as to what size Jeep used on their cases but it is more likely that you'll find a match if you get a t-case from the same year as your Jeep, and an even higher probability if you get one from the same year and from another ZJ. Also beware of the 21 Spline input shaft 231 case, as the ZJ only uses 23 spline cases. HTH <img src="/forums/images/graemlins/kewl.gif" alt="" />

Fred R.