Coolant is well below the MIN line. Should I flush and replace everything or just add? I would prefer to flush it all and replace everything just to be sure. Is one bottle of g12 mixed 1 to 1 with water enough to fill?

 

depends how big the bottle is. I got mine from the dealer 15 bucks for 2 gallons. more than enough.

 

Yeah flush it, also mine when I bought the g12 came in litres. I did 3 litres of g12 to 2 litres of water, a little stronger and totally legit as written on the outside of the bottles which gave me percentages and the degrees cooling difference for mixing stronger.