Good point Rodge .....
Generally the mix is referred to as eth-gly/water .... so 30/70 is 30% eth-gly.
But it only needs to be written or referred to once ... in the reverse - and its all out the window.
The ratio numbers have no real reference to the anti-corrosive additives, coz thats measured in teaspoons/tablespoons/whatever .... per litre of mix
.... regardless what the mix ratio is.
Which coolant grade to use ... and even which type is a drivers choice depending on what they know or whether they are warranty bound.
There is 4 sources of anti-freeze mix info ... Ooooops ... 5 sources ... thanks Nakkas ...
First is all the knowledge, beliefs, experience, opinions, facts AND fairy tales on car forums,
Second is the "our coolant is special
" drivel from the car manufacturers,
Third is what the "coolant
" manufacturers will tell you before getting to the point of upsetting the carmakers,
Fourthly there is the coolant scientific community ... who dont seem to give a toss who they upset when quoting facts and figures ... Coz they are always right ...
And lastly there is all those unchallangeable private websites with all their right AND wrong info.
I like to jumble it all together for a balanced view ....