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Have a 2006 Honda CRV. I have read so much about different makes of Anti-freeze ,silicates no silicates, borates etc.I don’t know what to think. Should I really only use Honda Anti-freeze or is that just a money maker for honda? I would like Tester to answer me on this as I have faith in what he says.

What does your owner’s manual say? Ask a local independent Honda mechanic for their opinion.


I used to think it was simple. No more. I would use the Honda antifreeze, avoid any possible problem (assumining it has Honda antifreeze in it now, if not flush it first).

How dare you even consider the “read the manual” option. (sarc)

The OP read the manual or at least knows that it says to only use Honda stuff. That’s what owner’s manuals say. They don’t say “but if you don’t want to pay for the OEM stuff you could just use…” The question is whether or not one must only follow the official recommendation.

I don’t know enough about Honda’s antifreeze or its recommendation. All I will say is that when in doubt, go with it. The extra cost is not really all that much - especially when you compare that to a problematic cooling system and associated engine problems.

just a thought. Couldn’t you find out what company makes the official Honda coolant. I seriously doubt Honda does. And just buy that formulation of that brand?

It appears that Honda uses a Hybrid Organic Acid Technology (HOAT) coolant. It uses phosphate compounds instead of silicates to extend the corrosion inhibiting properties. If you can find the MSDS for Honda Type 2 coolant, it will tell you what the main ingredients are (besides water).

To me it’s worth the few twenty bucks to ensure the correct coolant. Flushing the syetem is not something one does often. Why take chances?

But, since I’ve not inspired your faith, I’ll step back and let Tester answer.

This is one of the very few areas that the dealer actually tries to save me money. I have always changed my own antifreeze yearly…but long life antifreeze and alloy components make frequent service a thing of the past (like spark plugs). 100,000 miles and still the antifreeze is in excellent “shape”. So, if Honda is anything like my Toyota, and I suspect they are, I would do the Honda antifreeze thing as everyone says.

from Acura forum;

    • Silicates bond to the surface of the water pump seal and act as an abrasive, causing considerable seal erosion and coolant leakage. In actual tests, the silicated coolant caused early leakage. This leakage increased dramatically until a substantial portion of the coolant had been lost. In contrast, the Honda coolant had almost no leakage through the duration of the test.

Chart here, entitled “Coolant Leakage from Water Pump Seal”, showing Leaked Coolant Volume in ml as follows for each test duration in Hours:

24 hrs: Honda Coolant 0, Typical Silicated Coolant 21
48 hrs: Honda Coolant 1, Typical Silicated Coolant 36
72 hrs: Honda Coolant 2, Typical Silicated Coolant 47
96 hrs: Honda Coolant 2, Typical Silicated Coolant 55
120 hrs: Honda Coolant 2.5, Typical Silicated Coolant 56
144 hrs: Honda Coolant 3.5, Typical Silicated Coolant 57
168 hrs: Honda Coolant 4, Typical Silicated Coolant 58.8
192 hrs: Honda Coolant 6, Typical Silicated Coolant 63
200 hrs: Honda Coolant 6, Typical Silicated Coolant 64

    • Silicates tend to gel and settle in the coolest parts of the cooling system, causing radiator plugging and overheating.
    • Borates cause pitting corrosion on the cylinder head.
    • Silicate inhibitors are difficult to stabilize and, therefore, limit coolant shelf life.

So you’re suggesting a HOAT coolant?

Here’s an excellent article that will tell you more than you ever wanted to know about antifreeze chemistry, and who to believe: