Actually there are now a few alternatives, but I have always used Mopar ATF+4 in both transmission and transfer case. Whatever you pick, make sure it is the newer MS 9602 compatible. I also looked at a few other options and asked if anybody else had any experience with them:
http://www.ausjeepoffroad.com/forum/...ight=mopar+atf
Incidentally I went to the dealer Friday and picked up 4x4L bottles of Mopar ATF+4 at a price cheaper than any of the other options! I plan on doing a fluid change on my TJ and WG next weekend (long weekend in NZ). Check with your dealer and ask for a discount.