ATF IV is a group III synthetic transmission fluid that Chrysler has developed and licensed. I believe it also has a friction modifier in addition to other additives. As far as I know, Valvoline is the only aftermarket manfacture of the ATF+IV.

I understand that you could use Dextron, but need to ad Lubeguard to make it work...I personally would stay away from this method.

I am using Redline ATF C+ spec for my new Chrysler transmissions...Redline is an Ester based group V ATF. On a side note: Redline is not licensed ATF+IV, but it is the best ATF in my opinion.