Quote Originally Posted by hotshot View Post
Make sure you check the coolant. If it is red it still has the factory dex-cool wich cannot be mixed with the yellow stuff. If you need to add you have to add dex-cool or a certian prestone that will say on the bottle that it is safe to mix with any other coolant. Otherwise it will gel up and or turn into a sand like slugde and that will be a problem.
Green stuff cannot be mixed; if it is yellow it is supposed to be safe to add to any coolant. I have only seen the stuff made by Prestone.