Coolant fluid / antifreeze - 3gen V6 2.8 MPFI
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Coolant fluid / antifreeze - 3gen V6 2.8 MPFI
Hi All,
I have a few questions about antifreeze for Pontiac Firebird 2.8 V6 from 1988. I am based in Europe so please accept my apologies for asking silly questions, but I need some advice
1. What was the original fluid which GM used for this car? Was the fluid based on OAT (organic acid technology) or IAT (inorganic acid technology)?
2. Was GM using Dexcool for 3gen or was is introduced in mid 90s and used in LT1 engines only? Was Dexcool OAT based fluid?
3. Is perhaps a standard glycol based fluid (blue or green) more suitable for 3rd gen ?
I wanted to use Prestone which is universal , but I noticed that this fluid is purely OAT and I was wondering if it is not going to eat any seals in the engine/cooling system in 3rd gen.
Thank you for your replies
I have a few questions about antifreeze for Pontiac Firebird 2.8 V6 from 1988. I am based in Europe so please accept my apologies for asking silly questions, but I need some advice
1. What was the original fluid which GM used for this car? Was the fluid based on OAT (organic acid technology) or IAT (inorganic acid technology)?
2. Was GM using Dexcool for 3gen or was is introduced in mid 90s and used in LT1 engines only? Was Dexcool OAT based fluid?
3. Is perhaps a standard glycol based fluid (blue or green) more suitable for 3rd gen ?
I wanted to use Prestone which is universal , but I noticed that this fluid is purely OAT and I was wondering if it is not going to eat any seals in the engine/cooling system in 3rd gen.
Thank you for your replies
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Re: Coolant fluid / antifreeze - 3gen V6 2.8 MPFI
The original was the green stuff. (ethylene glycol) More of an alcohol than an acid. Not sure about "technology": it's been around for probably 100 years now. 
Dexcool "works" "fine", but the molecule is MUCH smaller, and it treats the gaskets in these older design engines more like a filter than a gasket. Because of that, and the problems that come with mixing it with the old stuff even in small amounts, I'd strongly suggest staying away from it, especially if this isn't a total rebuild with "dry" engine, radiator, & heater core.
Dexcool doesn't "eat seals". It just... leaks. Slowly, constantly, no matter what sealer you use or how tight the bolts are. It permeates the gaskets.
Not sure whether Dex was used in the LT1; but probably shouldn't have been, even if it was. (which may be the case for environmental and other reasons not related directly to "function") It was definitely used in all the LS series, and since those have rubber seals everywhere rather than paper gaskets, is much more appropriate to them.
Stick with ethylene glycol.
What you linked to is fine, except that it's a 50/50 mix. Which means, half of it is water. Which means, you're paying £16.94 a gallon plus freight, for ... water. Not a particularly good deal IMO. Buy the 100% kind instead for maybe £18 a gallon, and add your own £0.70 per gallon distilled (NOT tap) water.
Dexcool "works" "fine", but the molecule is MUCH smaller, and it treats the gaskets in these older design engines more like a filter than a gasket. Because of that, and the problems that come with mixing it with the old stuff even in small amounts, I'd strongly suggest staying away from it, especially if this isn't a total rebuild with "dry" engine, radiator, & heater core.
Dexcool doesn't "eat seals". It just... leaks. Slowly, constantly, no matter what sealer you use or how tight the bolts are. It permeates the gaskets.
Not sure whether Dex was used in the LT1; but probably shouldn't have been, even if it was. (which may be the case for environmental and other reasons not related directly to "function") It was definitely used in all the LS series, and since those have rubber seals everywhere rather than paper gaskets, is much more appropriate to them.
Stick with ethylene glycol.
What you linked to is fine, except that it's a 50/50 mix. Which means, half of it is water. Which means, you're paying £16.94 a gallon plus freight, for ... water. Not a particularly good deal IMO. Buy the 100% kind instead for maybe £18 a gallon, and add your own £0.70 per gallon distilled (NOT tap) water.
Last edited by sofakingdom; May 3, 2018 at 06:42 AM.
I will go for a green fluid based on glycol. 
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