So i want to do the np231 on my jeep but can't find any relevant videos on how to drop the case, found the video for the installation part...

 

I know for a fact that a 9/16 stuby ratcheting wrench will be your best friend.

There's 6 nuts that need to be removed. Kind of a pain in some areas. Dropping the crossmember and lowering the tranny a tad can help get around to the top ones a little easier.

Searched for NP231 Tcase removal on youtube...First hit. Weird.

 

Remove both drive shafts, disconnect shifter linkage, disconnect wiring, etc

Get a large floor jack. HF "rapid pump" is pretty good and inexpensive with coupon. Motorcycle jack looks pretty good too but might not go high enough. Put it under the transfer case.

Remove transmission cross-member, transmission mount, and exhaust bracket

If your engine mounts are in good shape then you can let the trans hang, otherwise use a jack stand under the transmission to keep from damaging the motor mounts.

Buy a stubby 9/16 flex-head gearwrench or cut a full-size in half. I like the full size too but you will need the stubby for some of the nuts

Disconnect the six bolts where the transfer case connects to the transmission

Slide the transfer case off. Don't let it smash the ground--the aluminum housing will shatter.

You will need a helper to reinstall, somebody to balance the transfer case on the jack and the other person to guide it into place. Put the transmission in neutral and the transfer case in 2WD, then rotate the rear output shaft to get the splines engaged.

 

Wow, time consuming, what's the estimate time for all this plus rebuild

 

The half moon 9/16 also is very helpful with top two bolts. It fits perfectly in the trans tunnel

 

First time took me nearly three days. Second time took 1.5 days. If I had a lift and a trans jack, I could probably do the whole thing in less than 8 hours.

 

31x10.50r15lt mickey Thompson Deegan 38's

 

Took me 5 hours to take the t case out, rebuild and install sye, and then put it back on and all this just on the ground without a lift

 

My rebuilds were replacing all the seals and bearings

 

yep. Not that hard to do