Tell me about NP242J to NP231J swap

[Mudderoy]

As many of you know I keep having problems with the chain stretching on my OEM NP242J transfer case. I think I can probably figure out what needs to be done to it to stop this issue, but I need more time than just a day, or a weekend, on the bench.

I've had several people recommend that I swap to the slightly stronger NP231J transfer case. Looking at ebay I see I can get one of these shipped to my house for under $300.

I have the Tom Woods SYE on my NP242J. So I would need a SYE from Tom Woods. I can ask them, but I thought you guys might know, would I need a different drive shaft? I think this can be answered by knowing if the NP231J is longer or shorter than the NP242J. I know I'll still have to check with Tom Woods since they would be providing a replacement main shaft and tail cone.

Would I need NP231J linkage? I know I should get a new plate to indicate the position of the shifter.

[4.3LXJ]

Match the type of SYE and you should be good to go, ie Tom Woods etc. As far as the linkage goes, you will need the handle and base plate so the notches will be in the right place. The rest of it should be the same

[Mudderoy]

Is there a difference? NP242J for a 98 Cherokee and a NP242 for a WJ?

https://www.ebay.com/itm/JEEP-GRAND-CHEROKEE-WJ-99-04-NP-242-4-0-6-CYL-TRANSFER-CASE-SELEC-TRAC-FACTORY/112717531976?epid=2055813973&hash=item1a3e7d0b48:g:mFkAAOSwYc5aRUDi&vxp=mtr

[4.3LXJ]

Now that is a good question. I don't know. Plan on indicator sensor plug for sure and no speedo cable. Uses a tone ring and sensor

[Mudderoy]

Here is the latest.

I am looking at the JBConversions.com NP231J HD with SYE. It has all the heavy duty upgrades you can do to the 231.

http://www.jbconversions.com/images/products/np231j/complete_stdsye-leadin.jpg

The Novak cable shifter, and a few odds and ends from ebay, bezel, shift plate(?).

http://www.novak-adapt.com/images/pics/linkages/kit_sk2xc.jpg

Spoke with Tom Woods about my rear drive shaft, and a HD front drive shaft. If I go with this transfer case, he's going to send me a new rear drive shaft, 1" longer than I have.

I'll send him my rear drive shaft and they will rebuild it and make the length correct for the front axle.

Now I'll admit, this is over kill, but damnit I'm tired of messing with this shit!

Thoughts?

[4.3LXJ]

I think you will be much happier with the 231. Simpler machinery is always better. And besides, it is all stronger stuff

[NC_Xplorer]

As far as transfer case shifter linkage, this is what I have, an Azzy's Design Works shifter linkage. I have to install it, but it is a much simpler setup vs. stock.
http://www.azzysdesignworks.com/store/jeep-np231-transfer-case-linkage-kit

Sent from my SAMSUNG-SM-G935A using Tapatalk

[denverd1]

As far as transfer case shifter linkage, this is what I have, an Azzy's Design Works shifter linkage. I have to install it, but it is a much simpler setup vs. stock.
http://www.azzysdesignworks.com/store/jeep-np231-transfer-case-linkage-kit

Sent from my SAMSUNG-SM-G935A using TapatalkJust finished installing Azzys linkage. TONS better than the stock crap.
https://uploads.tapatalk-cdn.com/20180203/97da283fd68ff81278c361c642f687db.jpg

Sent from my SAMSUNG-SM-G930A using Tapatalk

[4.3LXJ]

I love it. Simple and strong. What more could you ask?

[Mudderoy]

Two problems I see with the HD NP231 transfer case. The price and it still has a chain.

I'm considering another round of upgrades, and an Atlas transfer case may be the first step.

It has the same problem as the HD NP231, price+ but it doesn't have a chain.

Anyone that has gone the Atlas route in your XJ, thoughts?

[4.3LXJ]

As far as strength goes you cannot go wrong with the Atlas. Simplicity is another great strong point. One thing is that using one is a little different. I don't know about the new generation of Atlas, but the previous generation had very heavy duty synchros on all gears and it didn't shift at high speeds quite like a 231. And you cannot get it out of gear until the pressure is off the drivetrain. That means you have to get used to letting off the gas to get it out. I took my synchros out and it works much easier. One other thing is that making a clean shift linkage for the XJ console took some work, but I did it and made it look clean with a little ingenuity. I had to do some welding to make it happen

[Mudderoy]

As far as strength goes you cannot go wrong with the Atlas. Simplicity is another great strong point. One thing is that using one is a little different. I don't know about the new generation of Atlas, but the previous generation had very heavy duty synchros on all gears and it didn't shift at high speeds quite like a 231. And you cannot get it out of gear until the pressure is off the drivetrain. That means you have to get used to letting off the gas to get it out. I took my synchros out and it works much easier. One other thing is that making a clean shift linkage for the XJ console took some work, but I did it and made it look clean with a little ingenuity. I had to do some welding to make it happen

lol I had to start doing that with my NP242J after it got some wear on it. Had a habit (which I think is common) where it wouldn't come out of part time. Put the trans in neutral at 20 mph, coast, and push forward to 2WD. If the shifter felt spongy, it was still in part time.

Okay here she is boys...

14424

[4.3LXJ]

:congrats: When are they going to build it?

[4.3LXJ]

lol I had to start doing that with my NP242J after it got some wear on it. Had a habit (which I think is common) where it wouldn't come out of part time. Put the trans in neutral at 20 mph, coast, and push forward to 2WD. If the shifter felt spongy, it was still in part time.

The NP tcases only have a little spring to slip them out, that is why the lever will move and not disengage. With the Atlas, if the lever moves, it is out for sure unless you manage to break the linkage

[Mudderoy]

Atlas 2 speed ordered. Changed to 1300 series flange for the rear yoke at Tom Wood's recommendation to go to 1350 u-joints. I'll be buying a C 8.25 1350 yoke soon. Now to wait 5 to 6 weeks for the case to be built.

[4.3LXJ]

No drooling allowed while you wait :D

[Mudderoy]

No drooling allowed while you wait :D


https://www.youtube.com/watch?v=fhuBRZD-FMA&t=177s

[4.3LXJ]

I must say, they have improved the synchros since I got mine. Mine were pretty stiff, so i took them out. But it is all good :D

[Mudderoy]

Advance Adapters says May 15th for completion of the Atlas.

[4.3LXJ]

Start getting your exercise Tony, they are heavy

[Mudderoy]

Got the 1350 yoke for the Chrysler 8.25 in

14455

[4.3LXJ]

When you go to Wendy's, you can say "Here's the beef" :bacondance:

[Mudderoy]

Scott from Advance Adapters was nice enough to call me and tell me my Atlas was on schedule to be shipped tomorrow and even took a couple of pictures of it for me!

14468

14469

[4.3LXJ]

Doesn't that look pretty Tony? You can see the offset is much thicker than the 242. I suggest you take a BFH to the floorboard so you can mount it up far enough it won't hang down too far. That is what I had to do

[Mudderoy]

They actually have a 1998 Cherokee in their "How to install" on their site. They show the floor modification for the part you mention and (one way) to install the sticks. I like how they did it it almost looks factory. I don't think I'll have much trouble with it. I have a TC skid that I need to make it fit with.

14470

14471

14472

14473

http://www.advanceadapters.com/tech-vault/f-atlas-tc---xj-cherokee/

[4.3LXJ]

Wow, no installation instructions when I got mine. Things have improved

[Mudderoy]

Wow, no installation instructions when I got mine. Things have improved

Updated the post with the link to their "instructions"

[4.3LXJ]

You may find that the front axle shifter digs into your leg. It would mine. I made both mine short and straight for that reason. I haven't seen it, but there is or was a county sheriffs XJ that had the shifters coming out the side under the console. Ugh

[Mudderoy]

https://www.youtube.com/watch?v=NDVFIf229Rg

14508

14509

14510

[4.3LXJ]

Let the fun begin :D

By the way, the tool of choice for those nuts on the tranny tail housing is a stubby ratchet wrench. Makes it easy to get to the top and side nuts

[Mudderoy]

14511

[4.3LXJ]

Heavy isn't it? :D

Where is your site glass?

[Mudderoy]

Heavy isn't it? :D

Where is your site glass?

That tube, it's in a bag with some other stuff.

[4.3LXJ]

Mine came assembled. Better send it back :D

[Mudderoy]

Did you get a big ass sticker?

14512


Mine came assembled. Better send it back :D

[4.3LXJ]

If I did, I don't remember it. My ass remains stickerless to this day

[Mudderoy]

https://www.youtube.com/watch?v=Fbmrx2VXqMY

[Mudderoy]

I haven't opened it up yet, but this may be the reason for the stretched chain.

14516

Kind of hard to see but upper right, near center. Breather tube no hose. Is that normal? I was thinking it had a hose. I went through some pretty deep water on that flooding we had prior to harvey.

[Mudderoy]

14517

Half way there! Figure out the clocking tomorrow.

[4.3LXJ]

I don't remember mine having a hose either. That is why I suggest adding one to the tcase and linking it to the one on the tranny

[Mudderoy]

It's pretty high up, but if you brave the water it's a good idea. Would running the hose and attaching it to my snorkel be a good or bad idea?


I don't remember mine having a hose either. That is why I suggest adding one to the tcase and linking it to the one on the tranny

[4.3LXJ]

My philosophy on that is that the breather hoses, all of them need to be good for the highest water you intend to cross. In my case, I will not go into anything deeper than the hood, because after that the computer will get wet and that is the end anyway