It doesn’t take much to strip out the fill plug on the later split case. There are actual only a few threads on the upper portion of the whole to hold the plug. After much searching, I found my solution. The timesert is much like the helicoil or other thread repair products, except that it is a solid insert. While the fill plug, although a little tricky, can be done with the transfer-case installed. The drain plug will require disassemble of the case.
First is to drill out the old plug hole, then counter bore for the rim of the timesert.
Next you need to tap for the insert. If doing the fill plug with case installed I recommend using some petroleum jelly on the tap to capture as much of the shavings as possible, then thoroughly rinse and drain with brake cleaner.
Then you install the insert onto the installation tool. The last few internal threads of the insert are not tapped. Once you tighten the insert all the way, the last threads are cut and the insert is anchored (although I still applied some thread locker to the insert before installing).
There you have it, a strong steel thread for a good tight drain plug, don’t forget the new drain plug gasket/washer.
This is something I will be doing on any transfer-case rebuild in the future. If you would like this done on you disassembled case but don’t want to spend the $300 for the kit let me know. I will do this repair for about $30, but the T-case half needs to be sent to me. Contact me, or check out the page in my store, if interested.
Here is a picture of what is in the kit.
More pictures HERE