Thank you for the suggestion. I have considered this. But, I’m gonna end up just using Nissan’s pre-diluted 50/50 Blue Long Life Coolant.And this is just my opinion so take it for what it's worth (2 cents? 1 cent?) but since we live in CA, I recommend filling the new volume with only distilled water. No need to stick with 50-50 water-coolant mix in our climate. Distilled water has better cooling properties than engine coolant.