Gaffney982

Here's my deal. I have a 1995 ZJ, 4.0L, D30 Front (cv style driveshaft), D35 Rear, NP249 Transfer case and I'm looking to lift my jeep 3.5" - 4.5". The dilemma is this, would I have to swap out my NP249 for an NP231 or (preferably) an NP242 and I'd also want to get rid of the CV style front driveshaft and put in a yoke style one. I really would love to stay away from spending the extra money involved with installing custom driveshafts (aka Tom Woods) and an SYE. What kind of Jeep would I have to get a front driveshaft + yoke out to fit my ZJ and how involved is it to swap the transfercase? I would prefer to just directly swap out the old TC and put in the other one, but would that require changing the driveshafts anyway? IRO makes a nice 4.5" lift for $675 and that's within my budget but would a TC drop be sufficent enough to eliminate driveline vibration or would I have to add an SYE? I know that's a lot of questions but I figured there's no better place to ask than here. Thank you in advance!

Bustedback

I would swap it out just because of the reliablity of the NP249, it's not a good case. The NP242 is a good case, but the NP231 has more aftermarket support. You're going to need to swap out the front driveshaft and yoke, a boneyard will have the stuff you need.

North_Coast_ZJ

Just curious, does your NP249 Transfer case have a slip yolk on the front drive-line output shaft or is "slip" portion of it part of the front driveshaft? I have a 96 ZJ with the 4.0L, 242 T.C., with a Dana 30 in the front that has a single U-joint down by the differential and a Double Cardan by the transfer case . I'm not sure, but I think think it's the style driveshaft & the yolk looking for. I don't know what it takes to put the yolk on your differentail (crush sleeve, seals, ect), but the rest of it looks bolt on. I could take pictures of mine if it helps. As far as the transfer case drop goes, it's easy enough to try when after you've installed the lift if you think you need it.

Gaffney982

Not looking to get too aftermarket with this build. It's still gonna be my DD and I'm trying to keep costs down. Stock for stock, is the 242 better or should I go with a 231? If I get a front driveshaft & a yoke from a junkyard, would the yoke plug directly into my front D30? Should I be counting the splines on the yoke?

Gaffney982

I'm not sure what I should be looking for in regards to the front drive-line output shaft? I'm still very new to the Jeep scene so a lot of the terms you're using are new to me, I apologize. Down by my D30 it's the cv style driveshaft and it looks like a double cardon style going into the transfercase. I did a TC drop on my '97 XJ when I went up to 3.5" and that was easy and completely eliminated any driveline vibration. Can I modify my current driveshaft to eliminate the cv setup by the front diff or do I have to replace the whole thing and get a yoke coming out of the front diff?

North_Coast_ZJ

Pretty sure you do need to replace your front driveshaft, but I think you can use one from another ZJ that has a single U-joint down by the differential and a Double Cardan by the transfer case (like in the pictures below). You will need to replace the yoke on the front diff as well, but again that should be junkyard stiuff. I'm just not sure about the drive-line output shaft (the one that comes out of your transfer case on the 249. I'm not even sure if that's the right name for it , lol). You said you had the 249 T.C. and I'm showing you a picture of a my drive-shaft that's bolted up to a 242. I don't know if the driveline in the picture will bolt up to your 249, but I'm sure there a few folks on this forum that do. Good luck

Gaffney982

My front driveshaft is a double cardan by the TC and appears to be just a straight CV style shaft right into the front D30. I'm wondering if I can go the route of a NP242 by changing my front driveshaft replacing the yoke coming out of my D30

jeepcherokee99

Not to jack this thread but I have a 99 WJ and want to get rid of the cv boot style axels also. What would I all need and have to do?

po0dingles

I was getting ready to pull the trigger on a 3.5 inch lift and stumbled upon the whole drive shaft / transfer case issue.

I'm really confused.

I want this vehicle for daily driving and occasional mudding in south florida (not much rock crawling here). What do I need to do to install a 3.5 lift and keep things reliable?

I see 98 5.2L ZJ's came with the 249 transfer case and with 136,000 miles on her, I'm wondering what I should do in the event I need to rebuild my TC. Swap to a different one? When someone does a swap like that, how many book hours does a typical shop charge? What about the center console and knowing which gear you've selected???

At some point I'm going to need to do a rear main seal and service the transmission and may as well tackle the TC. I'm lost at this point as to what I need to maintain reliability and repair/upgrade parts to promote greater bulletproofing of the driveline.

When I look under my 98 ZJ 5.2L, I'm pretty sure I have the Double cardan-Rezeppa:


Front shot of front drive shaft:


Rear shot of front driveshaft:


Based on this image:

po0dingles

bump

North_Coast_ZJ

If I was doing it again I would buy adjustable control from the start of the project to keep drive-line angles correct.

I would think that a swap to a driveline with a conventional double cardan would probably be a good starting point with a 3.5". I'm sure a lot of folks are still running the 249 with a lift. Are you suspect that the vicous coupling in your t-case is going bad? Maybe some one else can chime in about the details of a t-case swap.

dnuccio

contrary to popular belief, the 249 is not a "bad" transfer case. it is the strongest of all the cases offered in the ZJ. the only downside to it is the viscous coupler that goes bad usually around 150k miles. replace that and youre good for another 10 years.