Replacing Old School Green

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Phosphate on the other hand isn't as good at protecting Aluminium and tends to create deposits....
The Asian vehicles I've used PHoat AFs in, the radiators have stayed pristine looking even at 100k+ miles. I have no idea the source of that information, but ime Phosphated Oat AFs do a great job of protecting aluminum with no significant or noticeable deposits over their recommended long service interval. And I don't read many issues on this subforum with folks using them in thier Asian vehicles. Usually the opposite in fact. That and the Asians vehicles, don't recommend or use silicates in thier AF. To topic, already been some suggestions, all which seem fine (none w/2eha). I'd likely do a distilled flush series before making a change, but that's just me.
 
It's the OAT part of the coolant mainly keeping the Alu pristine, not the Phosphate. Silicate undoubtedly protects Alu better than Phosphate. Silicates were not commonplace in automotive coolants until the manufacturers began using Aluminium heads and such, when they did they found that the old school Phosphate based formulas they were using did not protect Aluminium well.
 
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It's commonly known that silicates are very susceptible to silicate dropout/fallout. Old school green a prime example and it's been around a long time and used in non aluminum heads and blocks. In the US I'm unaware of old school IAT green using phosphate as the main inhibitor. Silicate drop out is a main reason that newer IAT AF like the aforementioned Zerex green is a low silicate formula. As is G-05 Hoat. As noted all the Asian vehicle manufactures prefer Phosphates to silicates. It seems the newer Prestone with CoreGuard found similar. So, based on my experience with Phoats and the Asian vehicle manufacturers recs I'll agree to disagree. As this is off topic, I'll leave it at that.
 
Modern Silicate containing coolants don't really have the dropout problem they used to have, there are compounds which control that and yes modern Silicate coolants have approximately a 25-30% lower concentration than they used to. VW for example went back from a full OAT ( G12 and G12+ ) to G12++ and their current G13 which use Silicates. But yeah let's leave this as it's off topic
 
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If G-05 is so great...... then why did Chrysler and Ford switch to Dex-Cool ? And you know that Dex-Cool doesn't have the best reputation.
 
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Originally Posted by Warstud
If G-05 is so great...... then why did Chrysler and Ford switch to Dex-Cool ? And you know that Dex-Cool doesn't have the best reputation.
Depends... Death-Cool clones contain 2eha, and will eat your cooling system/gaskets, unless they are meant for Dex-cool. Dex-cool ditched 2eha for awhile, and the problems went away for the gasket melting. Dex is cheap and effective, G05 is better but more expensive. Pre-Stool with 2eha will never go in anything I own or service, unless it's factory fill was Dex-Cool. 'Cor-guard' on the front, and 2eha on the back.
 
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2-Eha containing coolants are a bad idea if the original coolant that the engine came with did not use 2-Eha. Even more so if the engine in question uses soldered radiators in which case not only will the coolant swell the seals and gaskets it will also rather quickly dissolve the lead in the solder causing a leak. Non 2-Eha OAT / HOAT coolants on the other hand have shown to be ok in soldered radiators and don't seem to swell seals or gaskets.
 
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