Mixing OEM coolant with aftermarket

The PH test if done correctly will detect problems in the cooling system. The sad thing is most people just dip it and read it. That is not how you do the test with engines having aluminum and iron block parts as well other parts unlike years ago where the block heads and water pumps were all mostly iron..
You must first have a base line by knowing what the coolant PH specification are being used in the cooling system. This would be listed in the DATA information sheets of the coolant. Once you know that PH then dipping and reading after adjusting for the known PH will result in very accurate readings.
To my knowledge we don't have to worry about aluminum and iron block parts as the engine is all aluminum with steel cylinder sleeves which don't contact the coolant anyways. From a rust or galvanic corrosion standpoint, exactly what are the dissimilar metals that coolant is exposed to? Is even the water pump impeller steel or is it aluminum or non metallic. How big of a threat are we really having a discussion about. Anybody?
 
To my knowledge we don't have to worry about aluminum and iron block parts as the engine is all aluminum with steel cylinder sleeves which don't contact the coolant anyways. From a rust or galvanic corrosion standpoint, exactly what are the dissimilar metals that coolant is exposed to? Is even the water pump impeller steel or is it aluminum or non metallic. How big of a threat are we really having a discussion about. Anybody?
It is not a threat and there are dissimilar metals. My post was that a PH Test can indicate the condition of the coolant. Thats all. Sorry for all the confusion about doing a simple PH test.
 
I'd like to know where you all are getting your coolant.

The dealership here wants $40 a container.

And I'm in a fix.

My car went in for body work and was at dealers for almost 2 months. Got it back, drove it for a week and just noticed the coolant tank is low.
Should have checked it when got the vehicle back.
* Somehow by sitting at dealership the engine oil went from full line on dipstick to halfway. Not sure what's going on as never had this happen to any other vehicle I've owned.

So either they drained some coolant or my it's now seeping into the engine. Time for oil change and blackstone test.

In a pinch or would order it online from mazdaswag.

But it's now $40.

So either $40 or buy the zerex asian green premix for $20 to top off. I might just use zerex to fill it at this point.

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So I chose to pay the $40 for the Mazda oem fl22 coolant. I'm used to paying $3 and $5 for coolant for my Ford's so this was a priceshock.
But the cost is a drop in the bucket compared to Mazda potentially denying warranty work for not using their fluid. As their is still substantial warranty left and this model has engine problems, that is only reason using Mazda preferred fluid. After warranty, will switch to zerex or another quality substitute.

Still , Mazda fl22 is way more expensive than goldschlager. 🤔
 
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... So either $40 or buy the zerex asian green premix for $20 to top off. I might just use zerex to fill it at this point....
I know you've already solved the issue but how low are we talking? If you're trying to top up the little reservoir bottle and you're talking a few ounces, how bout door number 3 .... Add some distilled water?
 
I know you've already solved the issue but how low are we talking? If you're trying to top up the little reservoir bottle and you're talking a few ounces, how bout door number 3 .... Add some distilled water?
Nope it was down below the low mark... Not sure how it lost that much just sitting at the dealership. Doesn't make sense.
 
So as a top off, I'm using Mazda FL22 until the 7 year cpo warranty period expires. Reasoning is so that Mazda has no leeway/"out" to deny power train warranty work with the bad engine cylinder head issues

After the 10 year/120,000 mile mark, will probably switch to Zerex during flush. Reason being car is close to end of life.

As side note, according to an old Mazda service bulletin, the Mazda FL22 is supposedly guaranteed to last 10 year/120k miles. If you switch to another brand, no guarantee on coolant.

Again according to the 2007 Mazda SB, the FL22 is compatible with green ethylene glycol mix but the rating goes down to 5year/60,000 miles. Which also, may not offer as good protection for as long.
So probably not a good idea to mix or top off with another antifreeze.

$40 for a top off container and peace of mind is worth it until the warranty period runs out.

Now when flush, using zerex asian green at $18 a gallon x 4 gallons is only $72 versus $160 for the Mazda FL22. So...do you really want to waste $90 more dollars on a 10 year vehicle??? ***

*** For Miata owners , that answer may be yes. But this is an SUV. 10 to 15 years from now there will be a better more fuel efficient SUV, maybe with more power and with more features.
 
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Are you sure you shouldn't have used Zerex Asian green instead of Asian blue???
I changed out the factory fill at about the 6-1/2 yr mark using ZEREX ASIAN FORMULA BLUE (premix). Did a bit of 'research' and decided to go with it. It was available at Advance Auto a few blocks away for $15/gal with online order discount. Didn't have to drive across town to dealer or order it online. The original coolant was deep green , clear and very clean. No sediment in drain pan. I plan on a 5 year changeout schedule anyway which agrees with ZEREX' s recommendation and Mazda's schedule after the initial 10 year changeout. I don't forsee any problems. Now for transmission fluid it's Mazda brand only. That's a different animal.
 
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Are you sure you shouldn't have used Zerex Asian green instead of Asian blue???
I don't think there is a difference except for color. Maybe Advance Auto didn't have the green color at the time. And the blue indicates the original fill has been changed out and maybe it will give someone pause if they go to add something green of dubious origin. The factory fill was in for 6-1/2 years and the warranty expired and I really don't remember. It's been almost 2 years and it hasn't overheated or blown up yet. Like I originally posted, it's on a 5 year changeout schedule and from past experience the newer (which are not so new) formulations (as opposed to the old silicate formulations) are easy on the cooling system so no worries on my part.
Admittedly a long answer to your question but wanted to give some rationale for the decision. It's a used car now and though it will get quality parts, mostly OEM Mazda where it counts, in my book there are perfectly acceptable ( and more economical) alternatives for some things. Maybe even identical without the Mazda label. I seem to remember a throttle body gasket that was about $20 Mazda label that was about $3.50 under the Beck Arnley label and were identical including made in Japan. I've already chosen much cheaper and better performing brake pads from Raybestos. I'm sure the list will slowly expand a bit.
 
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