I have been trying to find the leak from my 727 since I have had it. I took it out and cleaned it and then let it sit and I found the leak on the back above the pan and below the tail shaft. It is leaking out of a dime size rod that i can push in with my finger. Is this rod supposed to move and does it have a o-ring on it.

The rod is the pivot pin for the rear band links, it has an O ring seal that often shrinks and leaks. As you have seen there is a tab on the tailhousing that prevents the rod from being pulled out enough to replace the O ring.

The down-and-dirty fix is to clean the area around the rod end thoroughly with brake kleen and cover the end of the rod with RTV. The fluid level in the trans must be drained below the level of the rod or the leaking fluid will prevent the RTV from properly adhering.

Goop it up and let it sit overnight before refilling with fluid.

I had the same problem on my 727.
I thought it was the pan,so I dropped the pan
and tried every type of gasket and just sealer.
Ended up being the same problem you found.
I cleaned the plug and used sealer on it,no more
leak.

https://board.moparts.org/ubbthreads/show...&PHPSESSID=

Went through same thing, link has the details.

How hard is it to take off the tail shaft?