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Prestone Extended Life Coolant - All Makes and Models

4371 Views 7 Replies 6 Participants Last post by  cadillacmike68
Hi everyone,

I'm a newbie here to the boards, just got a 1997 Deville with a few minor issues so I figured this would be the place to go for some help.

My main question here is pretty dumb...today, I went to AutoZone to get some coolant to top off the system. Happened to come across this stuff by Prestone, says it works with any make, any model, and any color coolant. I bought the 50/50 coolant distilled water mix version. Anyways, not even thinking about the whole Dex-Cool vs. Green coolant issue, I started putting it in to top off the system. I put in about a half gallon.

Is this stuff going to hurt the engine, should I get a flush and fill it back up? I came across this on Prestone's site so I'm not quite sure "Prestone® Extended Life 5/150 Antifreeze/Coolant has been approved by General Motors under their DEX-COOL® specifications and is compatible with other DEX-COOL® approved coolants"

Any thoughts would be appreciated. Thanks!
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Based on that I'd say you are OK. I don't think they could say"Approved by GM" if it wasn't.
Havoline is a dex-cool approved by GM. 1/2 gallon of what you put in shouldn't hurt anything.
ANY amount of silicate based coolant will interact with (mess up) the metal linings of the cooling system parts. This is why you can't switch from old silicate based coolant (the "green stuff") to Dex-Cool equivelant. The block and radiator, etc are already contaminated. Even a flush won't clean out the silicates. A complete rebiuld will but who wants to go that far over coolant type?
I'm not sure this stuff is silicate based. I was looking closer and it's actually more of a yellow tint than the typical green stuff. And it says right on the bottle that it is safe for metal and aluminum engine components and has been certified to work with all extended life coolants and will not alter their properties. On top of that...when I topped it off the coolant that came up to the the top was green in color. Now that I'm thinking, if the Dex-Cool had been in there in the first place, the color definitely shouldn't have been green. So I'm thinking maybe the person who I bought the car from switched from Dex-Cool to just regular coolant.
:stirpot: If you have a N* engine, given the uncertainty of your present coolant as described, I personally would do a complete coolant drain, flush, flush, GM/Barr's tablets in the lower hose, refill and bleed with new DexCool. There are threads in the archives above which describe the whole process. Takes a couple of hours and a rum and tonic. Enjoy.....BTW...describe your Cadillac in your profile - it makes diagnosis and advice much easier !!!
Prestone does say it's compatible with ANYTHING, ANYWHERE. Personally, I'd rather have the manufacturer's recommended stuff in the car. For example, the Cadillac uses Dex-Cool, or a full OAT, Organic Acid Technology, coolant. Our Chrysler uses a HOAT, or Hybrid Organic Acid Technology, coolant. There's a reason (I'm sure) that GM uses a full OAT and Chrysler a HOAT. If I'd listen to Prestone, I'd use their stuff in both. I'd rather not do that.

I will ASSUME that the Prestone Yellow coolant is a HOAT type of coolant, but you never know. That's why I don't use it ("you never know").
I'm not sure this stuff is silicate based. I was looking closer and it's actually more of a yellow tint than the typical green stuff. And it says right on the bottle that it is safe for metal and aluminum engine components and has been certified to work with all extended life coolants and will not alter their properties. On top of that...when I topped it off the coolant that came up to the the top was green in color. Now that I'm thinking, if the Dex-Cool had been in there in the first place, the color definitely shouldn't have been green. So I'm thinking maybe the person who I bought the car from switched from Dex-Cool to just regular coolant.
Hi, I was more responding to clallenger 71 than saying anything about the Prestone "any color" coolant. I sure that the prestone stuff is NOT silicate based, otherwise it wouldn't be "long life approved" etc... :confused: What I meant to say was don't just add a half gallon of just any old coolant into a dex-cool cooled engine, because you'll contaminate the whole system and will negate the "long life" properties because of the silicates in old fashioned coolants. There did I sufficiently confuse everyone enough? :stirpot:
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