PEAK extended life coolant now available for Chrysler

THANKS for the information.

When I see this, the hair on the back of my neck stands up. OAT is also what's used in Dex-Cool and in Prestone's red long-life stuff, and my experience has been awful (leaks, corrosion, gasket attack) using OAT coolants in '60s through '90s systems designed for conventional silicate chemistry.

From=20what I understand about G-05, it's worth consideration. I will *not* try OAT coolant again in a system not specifically designed for it -- I bought too many radiators and solder jobs and head gaskets and heater cores while doing so before.

DS

Even systems "designed for it" have had problems. Do a web search or two. "Contamination" is the problem,and it comes form sources like factory sealers, solder, air, etc.

Well - Prestone's "extended life" coolant is orange, and they recently got the second Dex-Cool license. I believe ACDelco coolant is likely just repackaged Havoline extended life.

The fact is that the majority of new cars come with silicate-free coolant using some sort of OAT. Not all are so-called "extended life" - Subaru would be an example. I'm not sure how compatible these are - Prestone claimed they've "lab tested" theirs for compatibility with various extended-life coolants. However - they seem to have removed this from their website in the past few days.

However - to be on the safe side, I've have a bottle of Prestone extended-life (I used Dex-Cool in my Integra) as well as Toyota Long Life Red. I'm going to get some premixed Subaru coolant too.

For clarification to my original post, the MOPAR and Zerex G-05 are HOAT (Hybrid Organic Acid Technology) coolants, not OAT. From what I can determine the difference is silicates. The HOAT coolants contain a moderate amount of silicates, which pure OAT coolants (e.g. Dex-Cool) do not have.

Apparently the lack of silicates in pure OAT coolants have been linked to water pump failures.

I'm not sure if either of these two PEAK antifreezes are HOAT or OAT. Neither MSDS discusses silicates, Zerex G-05's MSDS does. I am suspicious of the "PEAK® Global Extended Life Antifreeze & Coolant" because it claims to meet both Dex-Cool (OAT) AND the new Chrysler (HOAT) requirements.

It seems like it is real easy to claim a product meets a car maker's specification. It would be nice to see a verification of this. Until then, I would continue to use only Mopar Red Extended

Really - I keep on hearing that silicates are considered to be a cause of early water pump failures (when they start precipitating out). I've heard that GM's warranty claims for water pump failures went way down when they switched to Dex-Cool. Doing a little research, it sounds as if silicone (not silicate) is a water pump lubricant.

Silicates are supposed to coat and protect aluminum surfaces. However - it sounds as if the main problems with Dex-Cool have been in sludge building up in cast iron block engines running low on coolant.

I'm still a little bit dubious about extended-life claims.

A couple of things here:

If silicates are starting to precipitate out, then the neglectful owner who didn't keep the cooling system serviced deserves the nuisance and expense of a prematurely dead water pump.

Also, what is an "early" water pump failure, to you? I've driven a lot of cars a lot of miles on plain old ordinary changed-every-2-years silicate-containing coolants, and have experienced very few water pump failures, and those I have experienced have been minor leaks at high miles.

Dex-Cool attacks certain gasket materials and dressings, causing exterior and interior coolant leaks at the head gasket. It also attacks and/or fails to prevent corrosion of many solder formulations, causing leaks at seams and junctions in radiators and heater cores.

Me too. I do not advocate increasing expense and service hassle to cushion the stupidity of people too ignert to keep their cars serviced.

DS

I started using Dex-cool when it first appeared in retail stores and have never had any cooling system problems in it. All my cars since the mid-1980s have been Toyotas, 2 which had run conventional green antifreeze for a couple of years after the factory Toyota antifreeze had been changed. With the others I replaced the Toyota antifreeze directly with Dex-cool. Is Dex-cool actually that bad, or is the problem GM cooling systems?

If the industry info. is to be believed, I think what they're saying about HOAT vs. OAT vs. the green stuff is that the industry has discovered thru trial and error that *no* silicates is not the right answer, and that *a lot of* silicates is also not the right answer. There is a small amount of silicates which is the right amount that has some benefits without causing problems.

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

The question is not 'IF' the silicates will precipitate from a formulation. They DO and there is no way chemically to stop them.

As someone mentioned, the likelihood of it resulting in an observed problem may be a matter of degree, but the silicates will fall out no matter what is done.

Remember when we just used water in the radiator?

Ah, the simple life!

GM's current and recent cooling systems aren't really known trouble spots, but I can't comment directly; I don't own any GM products.

For a recap of the claimed problems with Dex-Cool, see

They also printed a letter they wrote to a Dex-Cool plantiff attorney at

HOAT is not OAT with silicates. They are different.

Other way around. Silicates cause the failures.

Don't buy any coolant that the manufacturer won't give you an MSDS for unless it's a "factory" coolant (they tend to hide them too).

Peak is playing games. They can't meet HOAT and OAT requirements with one product.

Only in certain water pump designs and under certain conditions. If the car was made for silicates, the pump will be fine.

I'm very leary of both OAT and HOAT antifreeze formulas. While I would not rush out and drain HOAT out of a new car and put in classic Prestone, one thing that I would *never* do is put a HOAT antifreeze in a car that didn't come with it originally.

That's not true. The predominant difference between OAT and HOAT coolants= are the silicates. OAT coolants rely soley on their organic acids to prevent cor= rosion and have not silicates. HOAT coolants also have these organic acids, how= ever they also have some silicates (but less than traditional coolants). That's w= here the word "hybrid" (the H in OAT) comes from. HOAT coolants are a moderately=

silicated hybrid between traditional silicated coolants (relatively high = amounts of silicates) and OAT coolants (no silicates).

Quote: "What?s a HOAT? Hybrid OAT in this case means it has a traditional Ethylene Glycol-base, with a single OAT inhibitor and is moderately silicated. The version now being installed by DC, and tested by Ford, is based on the German BASF product, Glysantin G 05. It has been used in extensively in European Mercedes Benz and other manufacturer?s vehicles since the late 1980?s. New users expect that it will provide the 5-year, 100K miles coverage they desire. G 05 proponents believe that its moderate dose of silicates provide greater aluminum protection than a straight OAT while still being water pump friendly." Reference:

Not in the cases I was discussing involving OAT coolants. There are no si= licates in pure OAT coolants.

The PEAK and Zerex coolants I have discusses have MSDSs readily available= , online at their respective websites.

True. So, is the "PEAK=AE Extended Life CF-EXL" coolant, HOAT or OAT?

As for the second coolant, "PEAK=AE Global Extended Life" it is marketed = as a top off fluid. If it is OAT and is only used occasionally to top off the flu= id, it may be relatively fine for both HOAT and OAT systems. Still, I wouldn't = use it in my (HOAT filled ) vehicle.

The traditional(green) stuff has a relatively high amount of silicates. That is claimed to cause failures. The DexCool?/Prestone Long Life? has

Am I right?

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

Almost all Japanese automakers at one time used silicate-free coolant meant to be drained every 2 years or 24/30K miles. They stressed the silicate-free part, because they claimed it screwed up their water pumps. They also supposedly used phosphate-based corrosion inhibitors. For example, Honda Type 2 (long life) coolant only claims to be silicate and borate-free.

It seems the European automakers stressed phosphate-free coolants. Something about typically hard water in Europe causing the phosphates to precipitate or something.

Then there's the new OAT coolants which try to appeal to the European crowd, as well as the Japanese automaker crowd. They seem to have gone without silicate, borates, nitrates, and phosphates. Whether or not it can work properly without silicates OR phosphates seem to be the debate.

One of the reasons the type of coolant on the Japanese cars of the era was so critical was that the radiator tubes were extremely fine (i.e., the inside oval cross-section height of the tubes was very small). This meant that even a slight build up of residue and/or corrosion inside the tubes greatly affected the flow and cooling capacity - it didn't take much at all to completey block the tubes. This was not true of the typical American car radiator, and there was significant reserve capacity in the size of the radiator, so build up and radiator performance degradation was not important except in extreme cases.

From my ownership of an '86 Subaru turbo wagon to 275k miles and considerable time spent on Subaru forums, it became understood within the Subaru owner community that the radiators would have to be replaced every 80k or so miles *if* the "American" type of coolants (i.e., the green stuff) and tap (not distilled) water were used. Aafter the introduction of the Extended Life? coolant into the AMerican market, the standard advice became to use only it and distilled water for indefinite radiator life (unless the external fins got clogged or corroded away, but that's another story).

Back then, Subaru, Toyota, and Honda sold their own "brand" of coolant at the dealer. The price was unbelievable - something like $10 or $14 a gallon. The typical American owner (including yours truly) assumed that was a gimmick - after all - antifreeze is antifreeze. I was told it was the low- or no-phosphates that was the key, but I still thought it was a gimmick. We all learned that it was no gimmick when our temperature gages started creeping up, with the nice side benefit with those engines that if you waited around to replace the radiator, you also would be replacing the cracked heads.

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")