G13 coolant in old GM?

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1990 GMC SL1500 4.3L 133k miles.
On a recent all day haul, at the end of the day the temp gauge moved towards the Hot zone a little farther than usual. About 3/4 between Cool/Hot. Never reached the red zone. Pulled over, cooled off a little. Checked coolant and it was nasty. Pure mud water. Wish I took a picture.
Anyways, today I decided to change it. And also thought that I'm gonna use whatever I have on hand, instead of going shopping for the "right" coolant. Hopefully that decision won't bite me in the arse later.
What I had on hand was Pentofrost E.
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Started by draining all the mud coolant from the radiator. Then refilled with garden hose water and a bottle of this.
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Ran the engine until it got to full operating temperature, and let it run at full temp with this cleaner for roughly about an hour. Heater was set on full blast, so I watched the temp gauge from the truck bed. All was good, so I proceeded to next step.
Since I had it on hand - I went ahead and installed Prestone flush kit on the heater core hose, while coolant with cleaner was draining.
Screenshot_20220629-192726_(1).png

Then connected the garden hose to the "T" from the kit, and ran the engine until water coming out of the yellow gooseneck was as clean as it can be. This step took over an hour.
Then drained the radiator again, and refilled with 3qts of Pentofrost E concentrate. Took it for a five mile drive, no issues. Drained radiator again and refilled with another 3qts of Pentofrost E. If my math is correct, then all things considered - I should be pretty close to a 50/50 mix.
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Took it for a ~20 mile ride. Tried to overheat it, but temp gauge stayed nice and cool. So I'm gonna call this operation a success. Let's see how long this success lasts. Figured that new "incorrect" coolant is still better than who-knows-how-old mud water that was in there... Or regular garden hose water by itself... Was I wrong? Any potential issues with using Phosphate-free G13 coolant in this vintage GM V6? Given how easy it is to change - I can always do it again if the threat is real. But if no huge red flags are present, then I may just run this coolant for next couple years.
 
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...But your positively charged Iron "ions" are going the cling to the chemically and negative plastic substrates leaching from particulates in the per-corrosion sub atomic interactions after phosphates eat-up what's left of the now gelled "old" micro fallout foaming inhibitors.... That and many other factors!

Seriously though... Don't ya' just wish there was just one coolant for everything?? BTW, switched ALL my vehicles to PEAK 10x to make life easier...
 

Graham Piccinini

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...But your positively charged Iron "ions" are going the cling to the chemically and negative plastic substrates leaching from particulates in the per-corrosion sub atomic interactions after phosphates eat-up what's left of the now gelled "old" micro fallout foaming inhibitors.... That and many other factors!
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Seriously though... Don't ya' just wish there was just one coolant for everything?? BTW, switched ALL my vehicles to PEAK 10x to make life easier...
Sure would be nice. Sometime ago there were some members here that switched all their vehicles to Toyota Red coolant (not Toyota Pink). I may have to dig up those threads and follow up to see how they like that decision long term. May end up doing the same eventually, but not anytime soon.
 

Graham Piccinini

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You're treating that old girl real nice. Looks like you're a truck guy now. (y)

Brake fluid next?
Current plan is diff fluid, then bleed brakes (along with new pads/rotors upfront), and fresh ATF with new tranny filter should complete the maintenance for now.
 
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Looks like it is a 2-EHA coolant from the MSDS. That seems to be a common ingredient in so-called "works with everything" coolants. Some say it that it is incompatible with certain types of plastics and silicon seals or gaskets that weren't designed for it. I would have considered a final flush with distilled water myself, although euro coolants seem to be usually formulated to work with hard water for some reason (ie; they don't have phosphates). I'd consider marking your reservoir with the type of coolant you have in it now. All that said, I'm still in the process of learning this stuff myself. Here's a link to the MSDS and a screenshot of one of those pages below;
Screenshot_PentofrostE.jpg
 
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Looks like it is a 2-EHA coolant from the MSDS. That seems to be a common ingredient in so-called "works with everything" coolants. Some say it that it is incompatible with certain types of plastics and silicon seals or gaskets that weren't designed for it. I would have considered a final flush with distilled water myself, although euro coolants seem to be usually formulated to work with hard water for some reason (ie; they don't have phosphates). I'd consider marking your reservoir with the type of coolant you have in it now. All that said, I'm still in the process of learning this stuff myself. Here's a link to the MSDS and a screenshot of one of those pages below;
View attachment 105959
That's one of the reasons I went with the PEAK 10X. No 2-EHA
 
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stop discriminating against a globally proven inhibitor package
Let me guess... You smoke Camels, work for Philip Morris and do side work for Monsanto.

Nope... not going to use anything with this product in it if I can help it. But everyone else is free to come to their own conclusions...
 
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stop discriminating against a globally proven inhibitor package
It seems to be widely accepted that 2-EHA can attack some plastics and silicones. No doubt OEMs that specify 2-EHA (dex-clone) coolants have avoided using those particular materials where in contact with coolant. That doesn't mean they aren't used in other vehicles or aftermarket parts. If it works for you, great. I wouldn't put it in anything that didn't originally specify it, myself.
 

FCD

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2-Eha definitely can be aggressive towards some plastics such as certain gasket or hose materials, and any coolant with 2-Eha does not belong in anything that has lead solder in the radiator as it attacks it
 
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2-Eha definitely can be aggressive towards some plastics such as certain gasket or hose materials, and any coolant with 2-Eha does not belong in anything that has lead solder in the radiator as it attacks it
so is sebacate that brutally attacks toyota FIPG later in life. go buy old car antifreeze like g05 or get with the times and buy a real radiator

the majority of passenger vehicles on the road are driving around on g12+ clones, dexclones, or g48. guaranteed
 
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What is the plus of G48 over G05 anyway?
Snippet of Zerex G48 spec sheet;
US_Val_ZXG48_AFC_HD_EN-crop.jpg


Snippet of Zerex G05 spec sheet;

US_Val_ZXG05_AFC_HD_EN-crop.jpg
 
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