Quote: Originally Posted by
dodgezdad 
Mopar atf+4 is a world class fluid [blend] and Chrysler licenses companies to use that name if they meet there standard.
I use atf+4 and the friction modifier and have over 75000 miles on my car with over 500 trips down the strip, most wot shifts and some people think I have an automatic.
Most modern fluids have the FM in it already [including atf+4] and are fine to use. Why Chrysler adds additional FM is unknown but I can assure you it is not to ruin your syncros.
I wouldn't ever say it's to purposely ruin your synchros. Just a negative side effect of it. I've tore many of these trannys apart, some beat on harder then others. The ones who have ran Mopar friction modifier for an extended period of time have always looked the worst, moreso on the blocker rings.
For the guy who asked, I use Amsoil ATF+4.
