"Good Bye" to good old "Prestone Green" traditiona

[Kenneth S.]

[Duke W.]

Re: "Good Bye" to good old "Prestone Green" tradit

I have some issues with this. The two major types of anti-freeze being used by the industry, today, are OAT and hybrid organic additive technology (HOAT). Inorganic additive technology (IAT) is considered obsolete.

The two camps are roughly divided as follows - GM, VW, and the Japanese OEs have gone the OAT route. Ford, DB, (and I believe most of the other European brands), and the HD diesel OEs are in the HOAT camp.

There is some discussion as to whether OAT should be used in older cars due to various solder issues, however, the general consensus is that HOAT is suitable for older cars.

Also, types should not be mixed, and especially if you switch to OAT from a car that was not originally so equipped, the system should be thoroughly flushed prior to installing an OAT type, and you should not "top off" an IAT or HOAT with OAT. I would limit any toping off to potable tap water until you can secure the proper antifreeze and distilled water.

Prestone was made famous by Dow Chemical, but they sold the brand long ago. The current owner is some company you probably never heard of, and they just contract with a major chemical maker to supply anti-freeze in bulk for retail packaging. Probably because the industry no longer uses IAT as original equipment, the demand is falling off, and it is becoming more expensive to produce.

A good widely available HOAT brand on the market is Zerex G-05, which is a Valvoline brand, and there are several brands on a market that meet the Dexcool spec including a current Prestone brand in a silver jug with an orange cap. Any brand that meets the Dexcool spec with say so on the label, and it requires licensing from GM.

Here's a link to the product data for Zerex G-05:

http://www.valvoline.com/pages/prod....asp?product=10

Click on the buttom: "Color and its significance" to download a very good PDF file that discusses the various anti-freeze technologies. Also, remember that all of these anti-freezes are ethylene glycol based. The different technologies distinguish the corrosion inhibitor chemistry.

I have been using Dexcool in all my cars including domestic, European, and Japanese since 1996 with no problems that I can attribute to Dexcool.

Duke

[Duke W.]

G-05 link correction

http://www.valvoline.com/pages/products/product_detail.asp?product=10

Duke

[Patrick H.]

Re: "Good Bye" to good old "Prestone Green" tradit

Duke,

Issues or not, it's coming. The new trend is ONE antifreeze. A lot of it is driven by the merchandisers who hate wasting floor space for 3-4 different TYPES of antifreeze (and even more brands) then having to explain it all to the customer as to which their car "might" need. A recent article in a merchandising newspaper gave me a heads up about a month ago.

FYI, I spoke with one of the DexCool engineers at the recent Windsor meet. In a nutshell he highly DIS advised ever using Dexcool in a system that previously had conventional antifreeze. In addition, if this was done without a complete flush with "b___" (I thought he said Boron, but that makes no sense) then you only had the 2 year protection, negating any perceived benefit. So, unless you go through the complicated flush he described or your whole system is new, don't change.

Patrick

[Duke W.]

Re: "Good Bye" to good old "Prestone Green" tradit

It will probably come down to two types on the shelf - OAT and HOAT, with IAT disappearing because no OEMs use it any longer.

Texaco, the original commercial supplier of Dexcool, NEVER claimed Dexcool would be suitable for extended change intervals in older cars that formerly used an IAT antifreeze. but at the same time, their claim is that it provides better corrosion protection, particularly for aluminum, and it will not continue to precipitate out salts that will clog the radiator and heater core tubes.

It is very tough for the industry to make any blanket statement about older model cars because their cooling system conditions vary widely, so they're recommendations tend to be conservative.

What were the engineer's specific reasons for not advising Dexcool?

In addition to Texaco recommending manufacturers' normal change interval for older cars that switch to Dexcoo, they recommend a thorough flush of the system to remove all liquid traces of the IAT antifreeze because there are some incompatibililty problems. Their flushing recommendation did not include and specific CHEMICAL flushing - just clean water. The presense of IAT components - prophates and silicates reduce the corrosion inhibitor capabilities of Dexcool.

Any system that has ever seen IAT will have IAT salts that have deposited on the cooling system surfaces and these will slowly dissolve back into the system, which is why Texaco recommends sticking with the OE recommended change interval on older cars that have ever had IAT coolants. Dexcool's long life properties are limited to systems that have never seen IAT anti-freeze. Nothwithstanding this, Dexcool will not preciptiate out more inorganic salts that will eventually clog our expensive aluminum radiators.

Duke

[Jon S.]

Re: "Good Bye" to good old "Prestone Green" tradit

Duke, so if we used the good old "green" in the past for our C1's, we now will select a HOAT antifreeze for these old cars?
Best regards, Jon

[Duke W.]

Re: "Good Bye" to good old "Prestone Green" tradit

That's beginning to sound like the best bet.

Duke