Antifreeze

scottsims1 wrote: Is 50/50 blend suitable for running during the summer or do I need straight antifreeze?

I have to assume you have a fresh water cooling system correct? Treat it like your car. NO on the straight without water. The stronger the mix, the worse the heat exchange. 50-50 is fine. It's in there for corrosion and NOT freeze protection. Did you drain it for some reason?

It is an 05 air with the zr6. I had to replace it all due to a bad impeller overheating.

The Dex-Cool was designed for cooling systems with aluminum components. Lots of controversy with problems with using it. There are even law suits against GM since it allegedly has caused so many issues. Personally, I would look for another brad designed for the aluminum.

scottsims1 wrote: So if I used the conventional 50/50 blend (green) your advice is to extract and fill with 50/50 pink ?

See page 36 in the URL below. It's your boat so put whatever you want in it., however PCM specified DEX-COOL for a reason (Aluminum heads.).

http://www.planetnautique.com/CorrectCraftManuals/2005/2005pcm.pdf

The issues (and law suits) surrounding DEX-COOL can be found with a quick search, Most problems with DEX-COOL stem from over extending its capability (owners left the coolant in longer than the recommended 5 years). Other issues known to cause problems include diluting the coolant by adding water, air entering the system, such as with leaks, contaminating the coolant with corrosive chemicals and minerals that can be oftentimes found in tap water, improperly mixing the coolant, at less than 50/50 concentration and failure to pre-mix the distilled water and coolant before pouring it into the system.

DEX-COOL has a five year life. After five years it should be replaced.

Remember to premix your coolant 50/50 before pouring into the cooling system (don't use tap water). Since coolant is considerably heavier than water, the two will not mix in the cooling system if introduced separately.