R&R Gearboxes without removing engine

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   Over the years that I have followed this forum there have been several questions about removing the Transmission and transfer case assembly. Should you do it one gearbox at a time? Should you leave the bell housing on the engine? Is it easier to remove the entire drive train in one piece? 
I have had many of these same questions and have tried most of the options. I thought I would post up step by step of how I like to get the gear boxes out. I'm doing this job to try and slow down some of the leaking that I have.

Before you start, its a good idea to take your jeep to the local car wash, or break out your pressure washer and try and knock what grease and mud you can off of the underside of your rig. This can make it so you don't get quite as much dirt in your eyes or down your neck. You'll still get some, but not as much. Doing it at the car wash leaves all that grease and dirt there instead of in your driveway.

Drain all the gear oil out of the transmission and transfer case. If you fail to do this step, when you actually get the boxes out you will have gear oil everywhere instead of nicely contained in your drain pan (don't ask me how I know this).

Disconnect everything under the jeep that is attached to the transmission and transfer case. 
This includes:
	-both driveshafts, I disconnect them from both ends so that I can get them out of the way.
	-stay cable
	-clutch return spring		
	-clutch cable that goes into the bell housing disconnect from cross tube (parts list calls this tube 	"lever and tube, control", but I'm calling it a cross tube.) 
	-clutch rod, disconnect from cross tube
	-unbolt cross tube ball stud from frame and remove cross tube
	-speedometer cable
	-Parking brake cable (mines gone so I didn't have to do this)
	_overdrive shift linkage if you have it.

Next I go to the top and start removing all the shift covers, the transfer case shift pin and levers, the overdrive shift lever, and the transmission shift tower. 
In my case removing the transfer case shifter pin is made quite a bit easier by a custom modification made by one of my uncles, a handy hole in the transmission tunnel that gives access to the shifter pin.

You can see the hole here in this picture. When I fixed the rusted out floor I considered closing up this hole but decided that it was too handy a modification to do away with. Someday I might make a cover for it, but probably not.

Here I have all the shifters and linkages stripped off. I can see here that part of my leaking problem is probably coming right from the shift tower. I hate really gluing that thing down because it's hard to get off, but I guess I'll have to try a different something to stop the leaking here.

Disconnect your negative battery cable (probably should have done this sooner, but I always forget), then disconnect the cable from the starter and remove the starter.  (you can see from this picture that I didn't follow my own counsel and wash things off first, lots of dirt in my eyes)

If you  haven't already, put your jeep on some jack stands and get it in the air a bit so that when you lower the gear boxes they will slide out from under the jeep without getting hung up on the frame, springs, body, exhaust, etc. causing you to use bad words that you don't want your grand kids to hear. 

Now I pull my floor jack over and put it under the back of the transfer case to hold the assembly up while I remove the cross member. 

First I remove the two nuts that hold the cross member to the transmission mount and the big bolt and nut that holds the cross member to the transfer case. 

Next I unbolt the two bolts on the vertical part of both ends of the cross member (4 bolts all together) leaving only the two bolts on the horizontal part of the cross member ends. (I think 3as and 3bs only have this one bolt and not the two vertical ones.) 

I now remove the two bolts on the horizontal part, leaving the drive train assembly resting on the floor jack under the tail of the transfer case. 

In this picture you can almost see my floor jack holding everything up.

Next task is to remove the top bolts on the bell housing to engine. I have tried several different methods to do this and hated most of them . I have removed the motor mounts to drop the engine down a few inches. I have twisted my hands into knots to get two end wrenches on the nut and bolt and only been able move it a fraction of a turn at a time.  This space is really tight, especially on the drivers side. 

I have discovered that if you lower the tail end of the transmission/transfer case assembly several inches with the floor jack previously put in place, it actually gives you enough room to get a socket with an extension (and sometimes a wobbly attachment) onto the bolt through the transmission tunnel opening. 

With the back of the engine a little lower as it pivots on the motor mounts, there is enough room to get a box end wrench on the nut side by the firewall. If you have a helper they can hold that wrench for you while you loosen with the ratchet, but I found that I could do it myself by putting the box end wrench on the nut and letting it hang there and then working the ratchet from the other side and when the nut comes off the end wrench just falls off to the floor.

Here's where my ratchet goes to get on the top drivers side bolt. The passenger side is even easier to get to. 

You will also notice in this picture that I cut a piece of cardboard to cover the transmission opening to try and keep at least some of the dirt and gunk from getting in there. I just used a couple of the tower bolts to hold it on. 

Next thing I do is prop up the back of the engine with a bottle jack and a piece of wood. I just lift the engine up enough to get the floor jack loose in the back. I like a little bit of downward tilt on the engine to make it easier for the bell  housing to clear the transmission tunnel as it's coming out and going back in.

Now get your transmission jack under there and snugged up to the bottom of the assembly. I have used my floor jack for this on several occasions and it works, but I like the transmission jack much better. Not so much of a circus act trying to balance the assembly on the little plate of the floor jack while jacking with my foot ...

Now remove the rest of the bolts holding the bell housing to the engine. I actually get them all out but one before I put the transmission jack in there, just because there is more room.

Now slide the assembly out. It always takes me some prying and muttering to get it out. This time I had the transmission jack a little too high and the assembly was on a bind and wouldn't come out until I lowered it a little. 

The assembly's  odd shape and awkward balance point make it hard to keep on the Jack so stay alert so you don't catch the thing on your chest when. and if, it rolls off the jack as you let it down. 

Here is the greasy lump in all it's glory. 

I like to stand it on the bell housing end and disassemble it from he back to the front. Standing it on the end keeps the transmission main shaft assembly from coming apart when you remove the transfer case and then dropping all the needle bearing in the bottom of the case (again, don't ask me how I know this .)

If anyone has any other tricks or additions that they would like to make to this, please feel free to add on. 

Grampa's Jeep is the one and only flat fender I have ever owned, driven, or worked on and all the above I have learned by putting the gearbox assembly in and out many different times, mostly because I didn't know what I was doing and had to take it back out to fix something I didn't do correctly the first time. So I'm sure that there are some more experienced heads out there that can correct anything I have mislead on.

I would especially welcome some input on what secrets you have for getting the transfer case shift lever pin out. Because of my custom pin access hole I have not had as much trouble with this process as some do. 