Atf

Sure - that stuff will be fine, just note that the stuff they use in the factory is a Dexron II ATF without the red dye - it is clear. You can pickup a bottle of that at the dealership for less than $2.50. Otherwise, just note that the Maxlife stuff will just mix with the existing fluid and you'll end up with a weird purplish reddish looking fluid. Functionally, it should be fine - so no worries there.

Another option is to bleed the system and refill completely with Maxlife. The advantage of that - you purge the system of old, worn out fluid - and you get the full protective benefits of the Maxlife formulation. Most power-steering systems never see any service in their lifetimes, though they recommend atleast a fluid change every other year or so - depending on driving conditions, to keep us the additive package and protect the power-steering system.