I'm learning as I go. Hybrid simply means that the coolant contains both organic and inorganic acids. Both silicates and phosphates are inorganic acids, thus Hybrids or HOAT coolants can contain either. Both PEAK Asian Blue and Zerex Asian Blue claim to use Organic Acid Technology, and both claim to use phosphate additives, which is an inorganic compound, which, by definition, makes both hybrid coolants, and if we are being totally accurate and honest, it technically means both are PHOAT (Phosphate-enhanced Hybrid Organic Acid Technology) coolants, regardless of how they are marketed, and therefore can be mixed. Please check behind me and make sure that makes sense. Jeeeeeeezzzz it shouldn't be this hard. And PEAK, which is clearly a hybrid, claims 15years/400k miles.
Asian Blue Coolant
- Thread starter Carlostrece
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Carlostrece
$100 Site Donor 2025
It sounds like Peak & Zerex Asian Blue can be mixed with each other. As for lifespan claims with Peak AB claiming 15 yrs and Zerex AB claiming 5 yrs, I'm going to try 10 years for each.
Am I OK as described above, or am I missing something?
Am I OK as described above, or am I missing something?
I emailed PEAK and asked if their Blue Asian formula was PHOAT, and if so, why was it only shown as POAT on their website, and wasn't it actually a hybrid. I actually got a call this morning, and don't feel like I got a straight, complete answer. To his credit, he acknowledged a lot of that terminology was used loosely for marketing purposes. However, he insited that what was meant by "Hybrid" was that the coolant contained organic inhibitors AND BOTH phostphates and silicates. I questioned that and repeated it back and had him repeat it to make sure that was what he was saying. It was. I don't think that's correct, but he insisted that PEAK Blue Asian was not a hybrid, but was POAT because it only contained phosphates and no silicates. I explained how the question arose about mixing Zerex Blue with PEAK Blue. He said that if you had filled up with PEAK and were just topping off with Zerex it wouldn't turn to gel or harm your engine, but he wouldn't do more than just a top-off, as there may be other ingredients and inhibitors that are not compatible. So, there you have it - still not a definitive answer by any means. The answer for me, at this point, since both PEAK and Zerex are readily available, along with a whole bunch of other brands, there is absolutely no reason to mix different ones. You'll only do a flush and refill every 3-5 years, and the difference in cost between the bargain stuff and the Manufacturer's stuff you get from the dealer is insignificant when spread out over a period of years, so just pick a brand you trust and don't mix them.
I do a drain and fill every other year. It makes it easy and plenty safe for any crazy rating they decide to print on the bottle.
The Subaru manual doesn't call for the first coolant replacement until 11 years or 137,000 miles. Going forward I will be doing it every 4 years.
Wow, Toyota has a similar crazy service interval and rumor is that it potentially causes early waterpump and headgasket death. Another thing that's probably impossible to prove but easy enough to avoid
Prestone’s Asian formulas are just a re-dye of Cor-Guard, which has been a pHOAT for a while. Else, Prestone would have labeled it as phosphate free.
I’m running the AMAM version in a Toyota currently. No problems. The Euros(and Tesla) want silicate in their coolants, hence why G-05/40/48 are still around.
Oh, and Prestone is now owned by Recochem.
I’m running the AMAM version in a Toyota currently. No problems. The Euros(and Tesla) want silicate in their coolants, hence why G-05/40/48 are still around.
Oh, and Prestone is now owned by Recochem.
Carlostrece
$100 Site Donor 2025
I see your point. However...
My reason to (potentially) want to mix them is I don't want to have to keep track of which brand of Asian Blue I put in each car. I just want to know it's either Peak, Supertech, or Zerex, or a mix of those. Also, I like to have the freedom to buy whichever brand is on sale at the 3 stores near me (Peak, Zerex, or Supertech).
Since Supertech Asian Blue is made by Peak, I assume they're equivalent.
I totally understand, sorry I couldn't clear up the confusion and come up with a definitive answer.
Carlostrece
$100 Site Donor 2025
Earlier in thread someone pointed out that Prestone Asian Blue contains 2EHA, if you care about that. For me it's a no.
I think Nukeman cleared it up well enough for me. I think Peak, Supertech, and Zerex Asian Blue can be mixed with each other, and they don't contain 2EHA.
The main concern is 2-EHA is aggressive with silicone. Dex-Sludge happened with GM’s 3.1-3.4L “high-value” V6s, the 3.8L Buick V6 and the Vortec versions of the 262 4.3L V6/350 used in their trucks. The factory GM IMGs were silicone on nylon, and Dex-Cool attacked the silicone beads on them. Mix that in with rust from an all-iron engine when air was introduced into the cooling system, you have problems. GM switched over to FKM(Viton) and steel gaskets, problem solved. Their Northstar and Ecotec engines seemed to handle Dex-Cool just fine, and the new at the time LS1 in the C5 Corvette and SS F-Body also didn’t have issues.
Toyota’s pink coolant uses sebacic acid, also a good plasticizer like 2-EHA is and it’s fairly common to see the RTV sealant on the valley plates of the UR/MZ engines leak. Water pumps on the 2GR engines were leaking for a while when Toyota first switched over to their pink coolant.
Cadillac Northstar coolant crossover gaskets would like to have a word. They are a very common leak spot. Either Dexcool ate them away or just another bad design to add to the list on Northstars
Aren’t the water pump gaskets on GM LSx/LTx engines a similar design or not quite?
I'm glad that is all cleared up for you! I've learned a lot from this thread too. I don't mean to hijack the thread, but I would still love a definitive, clear explanation of HOAT/POAT/PHOAT, free of speculation or contradiction. I also want to hit the lottery and look like Brad Pitt.
Carlostrece
$100 Site Donor 2025
I suggest you start a new thread asking about HOAT/POAT/PHOAT. Then you wouldn't be hijacking this thread. Also, you'd be more likely to get the detailed answers you seek in a thread that's about your question(s)
Thanks for your helpful suggestion.
POAT=PHOAT, same thing. Can be and is used interchangeably. Asian PHOAT, the P in it makes it a Hybrid OAT. I'd add another Asian PHoat to the list of no 2eha true Asian AF, Napa Asian AF. Peak OET Asian by another name. I frequently find it on sale for less others.
I'd add, unless a "very" recent change, Supertech Asian AF is made by Kost/Recohem. In my observation, they are less clear about "no 2eha" but Recochem is noted for making thier "OEM brand" Asian AFs which advertise "no 2eha".
The original Dexcool had 2EHA in it (and was an OAT) by design, so no one should be at all surprised that it works fine for an old GM vehicle. This example is irrelevant. I wouldn't worry about using it in an old GM either.
2-EHA is by definition a plastisizer. ie it softens plastics that are not designed against that. If you don't know what plastics you have, you don't know.
Making that same assumption for a Asian vehicle where the OEM never spec'd it in their history is quite different. Its not at all a fair comparator - either way.
This doesn’t agree at all with Prestone's take. They have their all-makes product and also a specific color product for each vehicle grouping, all of which contain 2EHA. I’m staying with Prestone and watch with amusement on all the repeated discussions on OAT, POAT, PHOAT, MOAT, ZOAT and what have you. But each to his own. I also don’t care what Europe does. Do not drink 2EHA. Flame suit on.
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Asian PHOAT, the P in it makes it a Hybrid OAT.
I agree, and that's what I posted earlier. Yet, the PEAK rep who called me insisted theirs was not a hybrid, and was not a PHOAT. That makes zero sense to me. I also got a 2nd email response from Zerex, after I questioned the first response as it was just c&p from their website, and contained all kinds if contradictory information. This one finally answers the question as far as I'm concerned:
Hybrid coolants are complex blends of chemicals, combining the benefits of older and newer coolant technologies to provide excellent engine protection and extended service life. Because different manufacturers might prioritize different aspects of protection or cater to specific vehicle requirements, the naming conventions can reflect these varied approaches.
There you have it: "naming conventions" can reflect different aproaches. IAT/OAT/HOAT/POAT/PHOAT are not industry defined standards, nor is there any agreed-to, industry accepted criteia fo defining those terms. Rather, they are general descriptive terms that different manufacturers may apply differently.
This all came about, in this thread, when someone asked if they could mix Zerex and PEAK Blue coolants. I had been told, and it's all over the internet, that different types/technologies should not be mixed. PEAK claims to be POAT (NOT a hybrid) and Zerex claims to be HOAT, clearly a hybrid. Therefore, it was my understnding that they could not be mixed . . . and down the rabbit hole we went, where I discovered that one company/website/guru says one thing, and another says something a little different, none of which resolved the question, and revealed that the designations HOAT/POAT/PHOAT are of little help when trying to figure it out.
