Have you run short on transmission fluid but don't see a leak? Check the transfer case. I was in the process of changing fluids among other major repairs. When I popped the fill plug on my transfer case to see if the level was maintained by the PO, I was caught off guard by about 1.5 quarts of fluid coming out. I didn’t understand how you can over fill this unit. Then with a little research I found if the input shaft seal is bad, transmission fluid will leak into it.

I read up on doing this myself and was a little apprehensive about it. Then @manicmechanic007 gave a bit of encouragement in another thread I have. I took the shot of encouragement and went for it.

The job is not for the faint of heart when doing it on the garage floor as opposed to a shop with a lift. If you do this there are some videos on YouTube University you can watch. My tips would be these.

1. Soak everything in Kroil, PB Blaster and Acetone/Transmission fluid for at least a day or two prior to beginning.
2. Be prepared with a torch. If using propane/MAPP, get one with the hose that goes to the bottle so you can have flexibility. The driveshaft bolts aren't coming out without heat. Neither are the torsion bar keys.
3. A transmission jack would be very helpful. I just welded an old brake rotor to an extra jack cup i had and it held the case just fine.
4. There is a frame crossmember riveted in place behind the torsion bar crossmember. Grind off those rivets so this can all be removed and out of the way. Scrounge up 4 bolts to put it back when done.
5. An air hammer will make life much more pleasant when removing the keys. I cannot imagine doing this with a hammer and punch after heating everything.
6. The front driveshaft was the hardest part for me. Those bolts did not want to move.

Also when buying seals. Know your case. Mine is a Borg-Warner 4406. It seems a 4416 was used too. Make sure your seal is for the right case. Since I had it out, I figured to do the rear tailshaft seal too. Destroyed the old seal getting it out only to find a 4333N seal is .06 inch too small. A 4333N is 2.704 inches and a 4503N is 2.765. Who'd of thunk it?

Tomorrow I will add fluids backend drive it. We'll see if I did it right!

 

Even more proud of you getting the keys off the torsion bars
That is NOT an easy job
Most people hack up the exhaust to get the T case out because the keys are so difficult
Those dual seal front transfer case seals are neat, aren't they?

 

I didnt do the front output shaft seal. I figure it was not leaking and did not see how the flange came off to mess with it. I wasnt cracking the case open! I had enough on my hands as i took the valve body out of the transmission and replacred the OD servo while i was under there. Did all the check ***** and put a heavy plate on it along with a pan that drains so fliud does not go everywhere. Changing all that did not help the harsh overdrive shift though.

If I ever do it again that riveted crossmember will go! The case just dropped off my jack getting it out and going back in required just laying on the jack base once it was close and manhandle it the rest of the way. That is a straight dumb design!

Yea, the keys got soaked daily for 3 days. That didn't help. I just got them as hot as I could with propane and let the Ingersoll Rand air hammer give it all it had.

When I took out the adjustment bolts the keepers had enough room to come out without having to twist the bars. I saw videos of people with jacks pushing the key up to relieve pressure one guys had a pipe wrench. I thought that was a good idea and had my big one at the ready but not needed. Are my bars shot?

I don't see where you can buy new ones anywhere.

 

No bars not shot
They make a special tool to preload the bar to install the key bolts
Make sure the front suspension is at full droop and than reassemble the keys and adjusting bolt
Look up F150 torsion bar unloading tool
That will put some pressure on the torsion bar key and allow you to install the adjusting block and bolt

 

No need for the tool. I just jacked up the front end and let the suspension drop as far as it would and the adjustment bolt (threaded piece that bridges the crossmember) just slipped right in. I saw the special tool and some people using a jack riged up with a steel rod but mine just fit.