This article is from the Chrysler-Plymouth-Dodge FAQ, by Dr. David Zatz with numerous contributions by others.
The FAQ maintainer notes that many people have destroyed their
transmissions by using the wrong fluid. Some people have had bad
transmission problems go away when they changed the fluid. Follow
Chrysler's recommendations to the letter. Ignore the alternative
fluid (as in "if Mopar is unavailable, use...").
See http://www.allpar.com/fix/trans.html for details.