So I know that some people say that they have had problems using other coolants besides the stuff from subaru. However, I just recently purchased my wrx and it had the 30000 mile service which is suppose to include a coolant change. The problem is that I checked the coolant level with the car being cool and it was a little below the L. So i thought ok, ill just add some coolant but the coolant in there is green and the dealer says i need the pink stuff? So wtf? Is it ok to just go ahead and add prestone green assuming thats whats in there?