3rd Gen Ram Tech2002-2008 Rams: This section is for TECHNICAL discussions only, that involve the 2002 through 2008 Rams Rams. For any non-tech discussions, please direct your attention to the "General discussion/NON-tech" sub sections.
To be on the safe side, I'd just buy the Mopar coolant and mix it with distilled water. It's not that much more expensive than after market coolants and you don't have to worry about any compatibility problems. I've had good results with Zerex's G-05 type coolant which is specifically formulated for Chrysler specs--gold colored jug typically found at Napa and Pep Boys. Whatever you do, stay away from Dex-Cool. Even though it's orange, it's a different formula. I mistakenly used it and wound up having to replace a timing cover gasket and water pump that it eat away. Dex-Cool is OAT and Dodge is HOAT.
depends what kind of climate you are in, if it gets cold and freezes there id be carefull about how much water you add. You can get the pink coolant at any auto parts store. Its an extended life coolant. I use penzoil coolant. Comes in a black jug, alot cheaper then mopar stuff and its just as good, never gave me an problems