I did a small research:
The freezing point of PG based coolants are slightly lower opposed to EG based coolants.
There is no significant difference in heat conductivity of EG and PG based coolants.
So, from this point of view no matter which one is used as coolant base, unless
you want to do some artcic coldstarts under -65 degree Celsius.
Anticorrosive additives (regardless of EG or PG based coolant)
- silicate and phosphate corrosion inhibitors: the "traditional" formula, protects
the aluminum and iron surfaces. Coolants with these additives must be replaced every
two or three years. IMHO the AAA classic coolant is using these inhibitors with PG.
- Organic Acid Technology: used to replace the silicate and phospate inhibitors for
longer service life (approx five years). Without special additives this type of coolant is
harmful to copper-brass parts (as AAA says)
- Hybrid Organic Acid Technology (G-05): uses organic acids too, but these are differs from OAT,
and it contains some silicate (to protect aluminum parts). Can be harmful to plastic parts which
not designed for HOAT (it's softens the plastic). The service life is similar to OAT.
Not recommended to top up (mix) coolant(s) with different inhibitor contents.
Last edited by LoneWolf33; 05-12-10 at 17:35.