The Jeep Cherokee transfer case is an essential part of the wheel drive system. The transfer case is separate from the transmission and can be easily removed for service or replacement. Here is how I did it last time I replaced one.
I began by draining the fluid by removing the bottom drain plug. Then I supported the transmission. Next I removed the front and rear drive shafts. An 8mm hex wrench and a pry bar was all that was needed.
I then unbolted the transmission mount using a 13MM socket. These nuts are inside the cross member and are accessed through the holes. Then I knocked the cross member by removing the 15MM bolts and nuts that held it up. That cave me access to the transmission mount that is held to the transmission by two 18MM bolts. These bolts have thread locking compound on them and are hard to turn all the way out. I monitored the mount which is often broken in high mileage vehicles like this one but it was fine. Next I folded the exhaust mount off the tab.
Rather than mess with the shift linkage bushing in the cold, I unbolted the shift lever from the transfer case. I selected 2wd and used a 9/16 wrench to remove the nut and washer. I carefully lowered the linkage out of the way. Normally I press out the linkage from the bushing. Unbolting the lever was easy so I may begin using that method as standard practice.
Next I removed the speedometer drive by unbolting the 13MM retaining bolt and removing the clip. I left the sender attached to the wiring harness. I dropped the harness away from the mounting tab on top of the case. I unplugged the mode light switch and moved the wiring out of the way.
Next, I unbolted the six 9/16 nuts that hold the case to the transmission. Five are accessed using a box end wrench. The last one is behind the transfers case shift linkage bracket and has to be accessed using a 9/16 socket and a long extension. The two near the exhaust pipe take some patience to get off without you remove the exhaust pipe. Since this one was in good shape and welded in place, I left it alone. Lowering the case down helps get access to these two nuts.
With the six nuts off, the transfer case slides easily off the transmission. I then prepared the replacement case to go back in by putting it in 4wd. This allowed me to rotate the front yoke and make the input splines turn to line them up. With the replacement case in place I started a nut to hold in there.
Next, I tightened all six nuts. I then reinstalled the shift linkage, wiring harness and speedometer drive. I put the case in 2wd to make the linkage line up with the lever. I then reinstalled the front drive shaft as it is easier to access with the cross member out of the way. I filled the transfer case with fluid before putting up the rear drive shaft as it is easier to get the bottle in place with out the drive shaft in the way. The 231 holds a little more than a quart of ATF.
I then put up the exhaust bracket and transmission mount. Again, these bolts are hard to turn due to the thread locking compound on them. I then put up the cross member and bolted it to the body before lowering the weight of the transmission onto the cross member. I then reinstalled the four nuts that hold the transmission mount to the cross member.
Then, I installed the rear drive shaft. I checked for leaks and loose bolts and then lowered the Jeep for a test drive. The replacement transfer case worked fine and shifted to all gears with out adjusting the linkage. If a linkage adjustment is needed, the loosen the 13 MM bolt on the linkage and slide it to the proper position.
