In the beginning...............lol
There was silicate based coolant, often green in color
The silicates protect metal parts from corrosion for about 2 years and needed to be flush and new silicates added.
Then came OAT(organic acid technology), often red or pink, this protected metal parts for about 5 years, then flush and add new OAT solution.
These two are not compatible, but both offer the same protection, so pick one and stick with it.
Then came HOAT( hybrid organic acid technology), they added silicates to the OAT solution so it will work in any cooling system regardless of previous coolant used.
This would be the "all makes/models" version, if you believe advertisers, lol.
And just as a heads up the "color" of the coolant has gone all over the spectrum so don't rely on it to determine what you are getting
While some advertise "lifetime" coolant I call BS, point being rad hoses and water pumps don't last a lifetime, lol, so my suggestion is to change silicate base every 2 years and HOAT/OAT every 5 years.
And silicates protect aluminum and other metal parts the same or better than OAT, the advertisers often claimed different when trying to sell OAT based products but the facts and long term testing don't show that, so it is strictly a matter of choice.
If an auto maker recommends a brand, other than one they own(LOL), then by all means follow the recommendation, but it would be for other additive reasons, not metal protection.
All anti-freeze uses Ethylene Glycol but that is a toxic(and sweet) substance so some now use "animal safe" Propylene Glycol, it isn't as good for very low temps but also won't kill your dog if you leave some on the ground or in a bowl after draining.
Either Glycol lasts, basically, forever it doesn't "wear out" so never needs to be changed, but see above, rad hoses and water pumps, lol.
Last edited by RonD; 10-22-2014 at 12:14 PM.