Did I use the wrong coolant?

[diesel_dave]

So I did do *some* research before I drained, flushed and filled my truck with Prestone Any Make Any Model green coolant. Apparently not enough research because now I'm reading that Prestone coolant is basically watered down Dex-cool that is dyed green instead of orange. I idiotically assumed that green = green when that seems not to be the case. I tried in vain to search this forum for an answer because I assumed this topic had been beaten to death but I turned up almost no results on what coolant to use. The TM just says ethylene glycol so that's not super helpful.

Do I need to drain this Prestone crap out before major damage is done from it not being silicate based coolant? I did flush very thoroughly with distilled water so there should be very little of the original dark green coolant in there. If it's not gonna cause any immediate concerns I'll probably leave it in there for a year and change back to conventional green unless y'all say to do otherwise.

Thanks!

 

[Coug]

Usually you only have issues when it wasn't thoroughly flushed. Dexcool does have a bad rep though.

That being said, if it was my rig I'd replace it. The coolant is relatively cheap compared to the cost of repairs to the cooling system if it does cause issues. It might not, but with Dexcool's history, not sure it's worth the risk.

 

[diesel_dave]

Usually you only have issues when it wasn't thoroughly flushed. Dexcool does have a bad rep though.

That being said, if it was my rig I'd replace it. The coolant is relatively cheap compared to the cost of repairs to the cooling system if it does cause issues. It might not, but with Dexcool's history, not sure it's worth the risk.

That's exactly my concern. Seems lots of people like zerex G05 so that's probably what I'll use even though it's pretty expensive. Still cheaper than a water pump, radiator or heater core though.

I'm still happy to get opinions from other people though.

 

[Autonomy_Lost]

I used prestone green when I replaced my water pump. In for answers.

EDIT: According to the Prestone Safety Data Sheet, it's mostly Ethylene Glycol:

https://prestone.com/wp-content/uploads/2020/11/SDS508-Universal-RTU.pdf

 

[diesel_dave]

I used prestone green when I replaced my water pump. In for answers.

Is that the same as the "any make, any model" stuff? There are so many variations, it's hard to keep everything straight.

 

[diesel_dave]

I used prestone green when I replaced my water pump. In for answers.

EDIT: According to the Prestone Safety Data Sheet, it's mostly Ethylene Glycol:

https://prestone.com/wp-content/uploads/2020/11/SDS508-Universal-RTU.pdf

I'm by no means an expert but I think the issue is the anti-corrosion additives that are used. Old green coolant used silicates where the Dex-cool stuff used a completely different compound that many believe attacked plastic, silicone seals, etc.

 

[Autonomy_Lost]

Is that the same as the "any make, any model" stuff? There are so many variations, it's hard to keep everything straight.

Yeah, if I recall it was labeled as safe for all makes and models. According to Prestone's website there really aren't that many options.

 

[Mogman]

I would think that you would not want to use any coolant with or compatible with Organic Acid Technology
If it was a "watered down" Dexcool it would be OAT compatible

 

[diesel_dave]

I would think that you would not want to use any coolant with or compatible with Organic Acid Technology
If it was a "watered down" Dexcool it would be OAT compatible

Just to be clear, you are saying you would not use this coolant because it is compatible with OAT coolants and therefore not ideal for a cooling system originally designed for silicate based coolant?

 

[Mogman]

Just to be clear, you are saying you would not use this coolant because it is compatible with OAT coolants and therefore not ideal for a cooling system originally designed for silicate based coolant?

YES, the OAT coolant is a completely different animal, cannot mix with or use in older engines not designed for OAT, so read the fine print, OK to say compatible with any "extended life" coolant but if it says it is compatible with OAT I would stay away, if it does not mention OAT at all or that it is not compatible with OAT then you should be good.

 

[Mogman]

This is the STP coolant I use in all my Detroit engines.

Product Details


STP 11098 Heavy-Duty Nitrite-Free Extended-Life Ready-to-Use Antifreeze/Coolant provides long-lasting protection with a high-quality formula that includes no phosphates, silicates, amines or borates. The coolant guards against cavitation and pitting to protect critical components. Thanks to a ready-to-use formula, the antifreeze requires no mixing or measuring.

• Antifreeze prevents pitting caused by cavitation and corrosion of brass, copper, solder, steel, cast iron and aluminum
• Extended service life up to 1,000,000 miles, 8 years or 20,000 hours of protection*
• High-quality coolant is free of phosphates, silicate, nitrites, amines and borates
• Compatible with most major OEM brands of extended-life coolant
• Ready-to-use - do not add water
• 
  
• This is the STP coolant I would stay away from...
• 
  
• Product Details
  STP 11096 Heavy-Duty Extended-Life Ready-to-Use Coolant/Antifreeze delivers up to 1,000,000 miles of protection to keep your vehicle running right. The antifreeze contains no phosphates, silicates or amines and helps prevent pitting and cavitation to guard against damage. with a ready-to-use formula, the coolant can be added quickly when needed.
  • Antifreeze prevents pitting caused by cavitation and corrosion of brass, copper, solder, steel, cast iron and aluminum to guard against damage
  • Extended service life delivers up to 1,000,000 miles, 8 years or 20,000 hours of protection*
  • Free of phosphates, silicates and amines for a high-quality formula
  • Compatible with all major brands of extended life Organic Acid Technology (OAT)-type antifreeze/coolant
  • Ready-to-use coolant - do not add water
  • *HD Extender may be needed based on test results
• 
  
  
  
  
  
  Ingredients
  
  Water, Ethylene Glycol, Diethylene Glycol, Denatonium Benzoate, Proprietary Corrosion Inhibitors

 

[diesel_dave]

YES, the OAT coolant is a completely different animal, cannot mix with or use in older engines not designed for OAT, so read the fine print, OK to say compatible with any "extended life" coolant but if it says it is compatible with OAT I would stay away, if it does not mention OAT at all or that it is not compatible with OAT then you should be good.

That's where the marketing mumbo-jumbo gets ya. The back of the bottle says its compatible with ALL types of coolant which is why I was initially fine with using it. However, based on the limited research I have done, that almost by the very nature of the chemistry involved, means that it isn't actually compatible with silicate based coolants. So now the question are, is that a problem when you have removed all the silicate based coolant from the system by flushing it thoroughly? Is an OAT coolant such as the Prestone AMAM going to do any damage to these engines?

The STP product you use, being "free of phosphates, silicate, nitrites, amines and borates" almost certainly means it is an OAT-based coolant, does it not? What else would they be using to inhibit corrosion? I need to do some more research on that one.

 

[diesel_dave]

The STP data sheet has the answer to the last question: "STP® Heavy Duty Nitrite Free Extended Life Antifreeze/Coolant is an Organic Acid Technology (OAT) formulation."

So it would seem that is an OAT based coolant.

 

[Mogman]

Those are some good questions, unfortunately I am not a chemist
If both of them were OAT technology then why would there be two different products

 

[Mogman]

The STP data sheet has the answer to the last question: "STP® Heavy Duty Nitrite Free Extended Life Antifreeze/Coolant is an Organic Acid Technology (OAT) formulation."

So it would seem that is an OAT based coolant.

Do any antifreeze sold now say they are silicate based?

 

[Mogman]

Also I have no idea if the Detroit would be happy with the OAT (red) antifreeze or not, OAT does attack certain plastics like what GM was using in their Gasser intake manifolds but I have no idea if anything in the Detroit that would be a problem, I do know that there are some that say "all will mix with any" in the industry but that has been proven incorrect, so it is said...
GM and others have of course corrected any issues with OAT and that looks like it is what everyone in the future will be using for a long time, at least until someone wants to feel important and comes up with some scheme that OAT is the end of the word as we know it..

 

[diesel_dave]

Those are some good questions, unfortunately I am not a chemist
If both of them were OAT technology then why would there be two different products

That's what makes this topic more complicated than it might seem at first glance and I guess why it hasn't been answered definitively anywhere that I have been able to find.

I found some article earlier that said Prestone sells the Dex-cool branded coolant separately and that the only difference is that is has more corrosion inhibitors in order to meet GM specs.

It seems like I should be looking for a coolant that uses IAT. Inorganic Acid Technology versus Organic that is used on modern vehicles. I am not sure if this article is trustworthy but it does seem to explain some things in layman's terms: https://gmb.net/blog/inorganic-vs-organic-coolants/

That website claims that IAT provides superior corrosion prevention for steel/iron but less lifespan so OEMs switched to OAT which lasts longer and is better for aluminum engines that are common these days.

So far, I am heavily leaning towards switching back to an old-school IAT based green coolant.

 

[Mogman]

Well crud,,,,,
You know it is ALWAYS something........
I think I will take my chances...

 

[diesel_dave]

Well crud,,,,,

We both might be completely fine with what we have in our trucks since we drained all the old OEM IAT coolant out before putting the new OAT stuff in. Or, it could substantially reduce the life of some/many components. I guess that is the million dollar question with the extremely elusive answer. Haha!

 

[diesel_dave]

I think my biggest concern would be the cast iron block corroding more quickly with OAT than it would with IAT. I know when I drained out the old green IAT coolant, it was 100% clean which was amazing to me. There wasn't a single flake of rust or crud that came out even though the truck has been sitting unused in a field for at least a year and probably longer. I guess when I drain this new Prestone stuff, I will see if anything comes out after being in there for a few weeks now.