What's the consensus on the best coolant to use for Subaru's? OEM coolant? I think the manual typically specifies high quality ethylene glycol?

 

I heard G-05 coolants (i.e. Zerex G-05) are excellent because they are OAT which provides a good layer of protection (but which may take a while to build up), and also have some silicate to provide immediate corrosion protection, but it's low silicate so there's not so much to precipitate out of it.

 

I suppose it goes without saying to use deionized or at least distilled water if any dilution is needed.

Mercedes? I know on the Saab boards Mercedes is thought of as the best. I've never used it so it's second hand information. It's supposed to be friendly to aluminum. It's pH adjusted and not horribly expensive considering it's for Mercedes. I personally run the cheap stuff with RMI-25 added every year. BTW, my dehumidifier in the basement supplies me with more coolant water than I'll ever use.

BTW, my dehumidifier in the basement supplies me with more coolant water than I'll ever use.

 

They produce distilled water?? Sorta makes sense, but wouldn't there still be crap in it

i dont think there is anything out there as a bad coolant. Stick with name brand, and use a 50/50 premix, this way the mix is never wrong. Change the coolant regularly and your head gasket, water pump and raditaor will love you. Check the owners manual (of other cars) as some cars can only use the OE coolant ( i know corvetes were like that in the more recenct years).

Water out of a dehumidifier is not deminerilized. It carries off minerals from the metal parts of the dehumidifier and also anything in the air. To properly get deminirilized water you need a reverse osmossis filter that is usually a two filters to get out all the salts and other impurities.

 

nipper

Dehumidifier water is fine for radiators if your dehumidifier has an air filter on it, as most do. Their are no minerals in it. You won't get minerals off copper tubing. Maybe a trace amount of copper, but I doubt it. Don't waste your money on demin water. You don't need RO quality water for a radiator.

I use distilled water to mix my coolant, but you may want to know that there is water available that is reverse osmosis. I know that when I used to work in a grocery store, we offered fill-your-own water that was purified by filtration and reverse osmosis.

 

Recently I have seen similar setups in Wal-mart grocery stores. I will continue to use distilled water, however.

 

I use name brand anti-freeze (prestone, Zerex, etc.)

 

Matt