pcsanady

I'm getting ready to add antifreeze for the first time to my vehicle since I've owned it. I know what you're supposed to use is "phosphate free" antifreeze. None of the stuff on the shelf I've looked at is labelled as "phosphate free," but they also don't list it in the ingredients. What is everyone using?

theedge

Ive used Prestone and Halvoline in mine, the orange "DexCool" type stuff. IIRC both are phosphate free, and one is free of other junk like Borites or something.

The other options are pink VW stuff, and I think the pink/red Toyota stuff is safe for our cars but im not sure. The VW and Toyota stuff are fairly pricey.

jjjr944

DANGER!

Mixing pink and blue is BAD!--------and not in a "Clockwork orange" kinda way. You WILL make Jello.

OEM
Blue/green--G11
Pink--G12

Know what you need or call the dealer. I can give you the 2 page speel out of the factory bulliten that VW published. 1980's to 1996 is Blue/green unless the PO has FLUSHED the system completely. Around 1997 and up is Pink.
Please chime in those that know and can guide more...

dualblade

i thought i heard some bad stuff about the dexcool. i'm hoping not, as that's what i have sitting on my shelf(but not in the car yet). can anyone comment good or bad about it?

JimV8

I was told dexcool was ok. IMHO coolant should be changed yearly anyway. Its like oil, cheap and plentiful so way mess around with old fluids.

Manning

Two of the most important things are:

1) not to mix coolant types and
2) not to use tap water, especially if you live in an area with highly mineralized well water or an area that has fluoride in the city water.

If you want to be on the safe side you should flush the cooling system and start fresh, since there is no telling what the previous owner put in there.

In the long run however, once you have the cooling system flushed it really doesn't matter which coolant you use as long as you don't mix them. No joke.

The fact is that the European auto makers recommend a specific coolant type because the water quality in Europe/RoW is questionable. Using coolant with (sodium) phosphate, which by the way is a corrosion inhibitor, mixed with highly mineralized water will cause the minerals to drop out and scale up on the hotter parts of the cooling passages. If you use distilled, though not ionized, water instead of tap water you will avoid this issue.

Another point to consider: Get all of the air out of your cooling system. If you have air in your cooling system not only might you have issues with air lock which prevents the coolant from flowing properly, but you may also experience erosion caused by cavitation. There was actually just a DriveWerk newletter that touched on that subject.

dualblade

very interesting manning. does that mean that with distilled water, phosphate coolant will actually be beneficial (for it's anti corrosion properties)?

theedge

Dexcool is fine as long as you dont mix it and the green stuff together. There you get a sludge. I think the bad things you heard about Dexcool is when its left in for 5 years... At least thats all I could find about it really. Im gonna switch coolant every year anyway.

If youre feeling rich, theres a waterless coolant that I hear is VERY effective. Ill try to find the thread I read about it.

Manning

Well, sodium phosphate is only one of several different corrosion inhibiting additives used in coolants. It honestly isn't the best corrosion inhibitor for aluminum parts, but it doesn't necessarily damage the parts like so many people are lead to believe. From an article:

"Common corrosion inhibitors include: sodium phosphate, sodium nitrate, sodium tolytriazole, sodium molybdate, sodium borate, sodium benzoate and sodium silicate"

From another article, aluminum is best protected by sodium silicate.

Thing is though, even if sodium phosphate isn't the best at preventing corrosion, it also isn't the only additive in the coolant. Chemical companies usually use a blend of salts, a corrosion inhibiting package as it were, to complement each other. Where one ingredient is weak in the package another is better.

What causes damage, other than mineral buildup, is when the corrosion inhibiting agents become depleted. As much as anything, this is why it is so important to flush you cooling system and replace the coolant on a regular, short, cycle.

peterjcb

I bought a couple of gallons of Zerox G-05 phosphate free anti-freeze recently at Auto Zone. It's the best choice for our aluminum engines.

jjjr944

Michael--i couldn't agree with you more-----DISTILLED WATER.

As for pink and blue, dealer OEM blue only in my 86 (but it works in my VW's as well). Choose the wrong one my pretty and it is merely more gold coin.

Chris_924s

I drink the green stuff, the pink stuff tastes weird.

oops -wrong thread.

Granite 944

I have been using Zerex G-05. Its available at almost any FLAPS, and, at least so far, is the only one easily found that I can verify on the label that it, 1: IS PHOSPHATE FREE 2: contains ETHYLENE GLYCOL (not propylene glycol).

I've heard lots of people say, it should be "silicate free" also. I don't know where that comes from, or why. I thought silicates were a good thing to have. Maybe not, but haven't seen anything in print about that. So far, I'm going with the info I've gotten from this TSB below. I'm not interested in going to any dealerships to get anti-freeze. Zerex G-05 is readily available, somewhat expensive (about $12.00 a gal.), and is what I'm using until I can find something better/cheaper/as convenient. I just would prefer something with a better/brighter color, that fits my above requirements, so I can see the level in the expansion tank a lot easier.........I'm kinda old.......ya know.

badass951

As Manning stated, sodium silicate is actually the additive in antifreeze that is used for aluminium protection (this I am 100% sure of). Also, ethylene glycol is actually just another term for antifreeze. Like others have said distilled water is the way to go, not tap water.

Another thing most people are not aware of is the fact that you need to mix the water and antifreeze prior to pouring it into the cooling system. With a 50-50 mixture of water and antifreeze you have protection to temperatures as low as -34 degrees Fahrenheit. Go as high as 70% antifreeze and 30% water and you will be safe to -84 degrees Fahrenheit (not that ANYONE on here should ever need that). Believe it or not 100% antifreeze will only protect to 0 degrees Fahrenheit.

Agreeing with Manning again, flush the system everytime, do not just add coolant.

Manning

Sodium silicate is actually the best corrosion inhibitor for aluminum based on the several technical articals I have read.

That tech bulletin is typical of a car company playing safe. Again, the call to stay away for sodium phosphate is based on:

1) the fact that while it is not brutally harmful to aluminum component, it also is not the best corrosion inhibitor for aluminum. It works, just not as well as silicate.

2) sodium phosphate will cause minerals to drop out of highly mineralized water. That is why you should always use distilled water.

One good thing about sodium phosphate being used in an inhibitor package is that it helps reduce cavitation and the erosion caused by it.

If you read the tech papers from all the chemical companies that make antifreeze, they all state that their basic product is suitable for all car BUT that you should use your vehicle manufacturer's approved product during the term of your warranty so that you do not disqualify your vehicle from warranty coverage.