Dexcool, JD Cool Gard 2, Peak, etc

[Carlostrece]

I have a 97 Buick Park Ave with 105K miles that I dearly love and want to take good care of it.

It has the stock type Dexcool in it. It looks orange to me or maybe reddish orange. I had it flushed and refilled with Dexcool premix around 8 or 9 years ago, which was around 4500 miles ago.

In a thread here a couple weeks ago, I was told that Dexcool is corrosive. It was recommended that I have my cooling system flushed again and then fill with John Deere Cool Gard II 50/50 mix. The second/alternative suggestion was to fill with Peak 50/50. It was suggested that I avoid Prestone and Oreilly house-brand coolants.

I went online today to buy 2 gallons of JD Cool Gard II 50/50 premix. I was shocked by the high cost. I was equally shocked by the low cost of Peak. Oreilly is medium price compared to those other two.

I'm willing to pay for JD Cool Gard II if it's better than Peak or Oreilly. Is JD Cool Gard II really better? If so, what is better about it?

How good is Peak, Oreilly, and other brands? Does brand of coolant matter? What color coolant should I switch to? I don't even know what color JD Cool Gard II is.

I've never before given any thought to brand or type of coolant in any car. I've always just replaced with whatever the stock color is using any brand.

 

[Escape08]

This is what I use for my Land Rover and Jaguar. Walmart's Super Tech Dexcool for $11.00. Never had a corrotion problem

 

[johnmyster]

Dexcool is fine, but five years is all I’d ask from any coolant. 28 year old car…buy it when it’s in special.

Flush and refill. Verify with hygrometer. Sleep easy for 5 years.

The JD stuff is good, but even it has been obsoleted by coolants with better (or more forgiving) corrosion inhibitors in the HD market.

 

[Trav]

Dexcool is not fine in the 97 Buick 3.8 or any other engine that utilizes a "wet" intake, it will damage the lower intake gaskets unless they have been replaced with the later aluminum frame variants. Coolguard II is very good in these engines and well worth the price for the protection in provides in mixed metal engines and cooling systems like yours. Flushing the old coolant out thoroughly is a must, I do it with the thermostat removed and lower hose removed.

 

[Sayjac]

If you've not experienced any issues with Dex to this point, imo no reason to change now. Look for Dex preferably in concentrate and stay with it.

 

[johnmyster]

Dexcool is not fine in the 97 Buick 3.8 or any other engine that utilizes a "wet" intake, it will damage the lower intake gaskets unless they have been replaced with the later aluminum frame variants. Coolguard II is very good in these engines and well worth the price for the protection in provides in mixed metal engines and cooling systems like yours. Flushing the old coolant out thoroughly is a must, I do it with the thermostat removed and lower hose removed.
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If we're going down the anti-2EHA route, then I'd have to change my recommendation to Peak Final Charge Pro.

I was under impression that ubiquitous modern dexcool is not the same as the dexcool 1.0 was 25+ years ago. If it were a problem, I'd expect it would've already surfaced due to the 8-9 year old mix in the system.

Here's a chart to help discern what-is-what in the HD coolants realm.

https://www.owi.com/binaries/conten...-documents/hdaw-2023/peak-hd-afc-brochure.pdf

Peak FC Pro is available at Walmart for $16 a gallon, premix. Also available at tractor supply and all my local parts stores. Napa puts the concentrate on sale for $17 a gallon every few months. Universal availability is the basis of my recommendation if 2EHA avoidance is necessary. At one point Peak 10x was non-2EHA but rumors are that this has recently changed.

 

[Trav]

Dexcool still contains 2-Ethyl Hexanoic Acid aka 2-EHA. This product is being banned in other countries, it is not good stuff.

Due to reform of the European Chemicals Agency, a classification and labeling of many radiator antifreeze products will change this year.

As a result, products containing 2-ethylhexanoic acid (2-EHA) as a corrosion inhibitor may no longer be sold over the counter. These products will then fall under the Chemicals Prohibition Ordinance in Germany.

If you've not experienced any issues with Dex to this point, imo no reason to change now. Look for Dex preferably in concentrate and stay with it.

Do we know if the original intake gaskets have been replaced since 1997?

 

[Carlostrece]

Dexcool still contains 2-Ethyl Hexanoic Acid aka 2-EHA. This product is being banned in other countries, it is not good stuff.

Do we know if the original intake gaskets have been replaced since 1997?

Not yet. I might eventually have the gaskets changed, but I'm currently sick and have an upcoming heart operation 2 weeks from now. I don't know if, or when, I'll get the gaskets changed. Hopefully I will eventually.

What I can do for sure, and do it soon, is get coolant flushed and changed.

 

[Carlostrece]

If we're going down the anti-2EHA route, then I'd have to change my recommendation to Peak Final Charge Pro.

I was under impression that ubiquitous modern dexcool is not the same as the dexcool 1.0 was 25+ years ago. If it were a problem, I'd expect it would've already surfaced due to the 8-9 year old mix in the system.

Here's a chart to help discern what-is-what in the HD coolants realm.

https://www.owi.com/binaries/conten...-documents/hdaw-2023/peak-hd-afc-brochure.pdf

Peak FC Pro is available at Walmart for $16 a gallon, premix. Also available at tractor supply and all my local parts stores. Napa puts the concentrate on sale for $17 a gallon every few months. Universal availability is the basis of my recommendation if 2EHA avoidance is necessary. At one point Peak 10x was non-2EHA but rumors are that this has recently changed.

I'm not going to weigh in on which coolant is better because I don't know. However, I will say that Peak 50/50 is widely available for $10 gal, or Peak Pro 50/50 $14. I don't know if that's regular or sale price. Peak also has other product names of coolant. At this time I don't yet know which Peak product I should get, if I get Peak.

John Deere Cool Gard II 50/50 premix is $28 gal at Walmart, which is the lowest price I've seen. It is widely available from other stores locally and online, but at much higher prices. So for getting a somewhat decent price, it's not widely available. Luckily though theres plenty of Walmarts, but Walmarts are not convenient or time efficient.

I know buying concentrate & distilled water and mixing it would cost less, especially if having it shipped. The prices above are for comparison.

I'm looking for good longevity for my car with my original gaskets. So if JD Cool Gard really is signifigantly better than Peak, then I'll get what's better. Also, considering my health, this might be my last ever flush and refill. So it needs to be good stuff to last as long as possible.

Are there other brands that I should consider?

 

[johnmyster]

I'm not going to weigh in on which coolant is better because I don't know. However, I will say that Peak 50/50 is widely available for $10 gal, or Peak Pro 50/50 $14. I don't know if that's regular or sale price. Peak also has other product names of coolant. At this time I don't yet know which Peak product I should get, if I get Peak.

John Deere Cool Gard II 50/50 premix is $28 gal at Walmart, which is the lowest price I've seen. It is widely available from other stores locally and online, but at much higher prices. So for getting a somewhat decent price, it's not widely available. Luckily though theres plenty of Walmarts, but Walmarts are not convenient or time efficient.

I know buying concentrate & distilled water and mixing it would cost less, especially if having it shipped. The prices above are for comparison.

I'm looking for good longevity for my car with my original gaskets. So if JD Cool Gard really is signifigantly better than Peak, then I'll get what's better. Also, considering my health, this might be my last ever flush and refill. So it needs to be good stuff to last as long as possible.

Are there other brands that I should consider?

Yes. Peak final charge pro.

 

[Trav]

Not yet. I might eventually have the gaskets changed, but I'm currently sick and have an upcoming heart operation 2 weeks from now. I don't know if, or when, I'll get the gaskets changed. Hopefully I will eventually.

What I can do for sure, and do it soon, is get coolant flushed and changed.

I hope you OP has a good outcome for you. I cant comment on any other coolants as JD is one I have used for over 15 years, 12 of them in a GM 3800 with no corrosion or any issues.

 

[Sayjac]

If you want to go the no 2eha AF route instead of Dex, two I'd recommend. Peak Global Lifetime, no 2eha OAT AF. So like Dex an OAT AF minus the 2eha. Also, Zerex Original Green Low Silicate AF, IAT tech. 'I'd' likely go with the former first.

 

[Carlostrece]

I hope you OP has a good outcome for you. I cant comment on any other coolants as JD is one I have used for over 15 years, 12 of them in a GM 3800 with no corrosion or any issues.

Thank you Trav. I appreciate your help and advice. I might get JD Cool Gard II, but due to its greater cost and lesser availability, I wanted to explore the coolant topic more thoroughly before buying coolant.

 

[Carlostrece]

Keeping in mind my health situation... I can and will flush and replace coolant soon. I don't know when, or if, I'll ever be able to replace again. I might never be able to replace gaskets, but nothing is leaking so far.

So I want to replace with new coolant that will be compatible and non corrosive with my 97 Buick Park Ave original gaskets so that my car and original gaskets will last as long as possible. Also, I need the coolant to last as long as possible before needing to replace it again because replacing coolant is a difficult ordeal for me.

I might become phyically or mentally unable to get coolant flushed and replaced again in future. So I need to make a wise choice for this flush and replacement.

The cost of the coolant is the least of my concerns, but I do care a little bit about cost and availability. Quality and longevity are what I care about most.

It sounds like the main contenders are Peak Pro, Peak Global Lifetime, and JD Cool Gard II. Is that correct? Do you guys have any other info or suggsstions to help me choose?

 

[Carlostrece]

John Deere Coolguard II needs changing every 5 years?
Peak Pro needs changing every X years?
Peak Lifetime needs changing every X years?

 

[Nukeman7]

John Deere Coolguard II needs changing every 5 years?
Peak Pro needs changing every X years?
Peak Lifetime needs changing every X years?

Like Trav said, avoid the coolants that contain the 2EHA content if you still have the original lower intake manifold gaskets made of plastic. 2EHA is a known plasticizer that will soften and degrade plastics. If you can find some old stock, I suggest going with the old PEAK 10X (not the new 10+) labeled formula. PEAK 10X is advertised as a 10 year coolant.

Check out this BITOG Coolant Thread from a few months back.

 

[Carlostrece]

Peak 10X (not 10+) 50/50 premix is currently available at Harbor Freight for $9.79 gallon in-store-only or Amazon Prime for $11.69. We don't have an Ace in my local area anymore. Though come to think of it, there's an Ace in my cousin's home town. I'll have him look at Ace too.

John Deere Cool Gard II 50/50 premix is available from Walmart for $28 gallon.

If my cousin finds it cheap at Ace, or if I can get my neighbor to drive me to Harbor Freight, then I'm going to buy 3 gallons of Peak 10x 50/50.

I'm not able to drive a car anymore, but I still try to keep my car as well maintained as possible because I ride shotgun when family or friends drive me around in it. There's nothing worse than getting stranded in the winter when I'm sickly and handicapped. So I try to keep my car reliable.

I just read the other thread about Peak 10X. That was very helpful info. Thanks everyone, and especially Trav and Nukeman7.

 

[Nukeman7]

The old PEAK formulation will show "10X MORE" at the bottom left corner like this:

The new formula with 2EHA will not state "10X MORE" anywhere, just "10+ Years" in the lower right corner:

Yellow cap & label is 50/50% pre-mix; red cap & label is 100% concentrate.

 

[Sayjac]

Peak 10X (not 10+) 50/50 premix is currently available at Harbor Freight for $9.79 gallon in-store-only or Amazon Prime for $11.69....

The reason I went Peak Global Lifetime is because 10X is now discontinued so getting harder to find and will go away. Also, must be very careful that the jug definitely has the X on it and not a 10+ because two different AFs. The latter is the old Peak Long Life AF which uses 2eha. Very confusing and very poorly done imo on Peak/OW part.

But, if you can find 10X definitely a no 2eha option. That said, PGL especially if found in the concentrate, is a long time bitog favorite and still a very solid option. And Amazon now sells it in concentrate for ~$20, not bad.

As for my initial Dex recommendation, my thinking there was if vehicle gone this long on Dex, how much more harmful can it be. Also, the issue with early GM cooling system goes well beyond simply Dex use. The OE GM LIM gaskets were of such composition that Dexcool apparently affected their longevity. Add to it GM angle neck radiator fill openings which made it all but impossible to fill to the top and allowed more air in the system contributing to "Dex sludge". All factors to the early GM cooling system issues often attributed solely to Dex use.

 

[Carlostrece]

My thinking is that Peak 10X is still available locally and online for very discounted prices. I can buy 3 gallons of Peak 10X 50/50 for the cost of 1 gallon of JD Cool Gard 50/50.

I know new oil eventually goes bad sitting around in it's jug if you store it too long. Would that also happen with Peak 10X if I stored a jug for many years?