I was given some interesting information by a friend of mine who was a Jeep mechanic (dealership) during the Renix era and beyond. He told me that Chrysler released a TSB in 1994 which stated all Chrysler vehicles could use their newly developed ATF+4 fluid in place of the older standard Dex/Merc II & III. However, the TSB specifically excluded the AW4 from this substitution. In 2007, Chrysler released another TSB which basically stated the same thing but did not exclude the AW4.

A couple of observations. 1.) In 2007 all AW4 transmissions would officially be out of warranty and thus, no longer the responsibility of Chrysler so their service department could potentially benefit from this. They could have recommended that you use extra-virgin olive oil, what did they care? If your transmission blew up you would bring it to them to have it fixed and you would be paying for it. And 2.) Chrysler had a vested interest in switching people from Dex/Merc III to ATF+4 since they held (and still hold) the license for ATF+4, they would profit from it's sale.