Which extended life coolant for a '95 Buick Skylark?

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If you talking about intake manifold gaskets, isn't that a myth that has been disproven long ago? They were failing with green coolant just as much.

Even though LIM may have failed with green coolant, the sludge is unique to dexcool and didn't happen with green. GM eventually switched to a pressurized coolant tank. For the N-body, I think that happened in 99 when the next gen came out.

At the very minimum, don't use Dexcool unless your car has a pressurized coolant reservoir.
 
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What do you mean pressurized coolant reservoir? It has a cap on the reservoir saying 15 psi.

I did not know that! I thought they had started using the pressurized caps later, when GM actually started filling with Dexcool from the factory. I know there are at least some Dexcool-era cars that didn't have the pressurized reservoir yet.

In your case, you might be OK with Dexcool, but I'd still pick 10x over it.
 
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prestone

american green antifreeze in any application = no
This isn't the Old School green that you had to change out every year or so
Screenshot 2022-04-05 at 18-28-05 Zerex Original Green Concentrate Antifreeze - 1 gal ZRX ZX00...jpg
 
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Even though LIM may have failed with green coolant, the sludge is unique to dexcool and didn't happen with green. GM eventually switched to a pressurized coolant tank. For the N-body, I think that happened in 99 when the next gen came out.

At the very minimum, don't use Dexcool unless your car has a pressurized coolant reservoir.

The Sludge or what I always called "Red Mud" was caused by adding incompatible coolants to systems with Dexcool.

Dexcool is a outstanding coolant & will outlast conventional green coolants by a wider margin than advertised.
 
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So I'm safe to convert after a total removal of whatever is in there now?

Absolutely, Have run Dexcool is every vehicle I've owned for the last 20 years as I hate having 5 different coolants in my garage & Dexcool seems to have better availability than other long life coolants.
 
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Zerex G-05 coolant, and add two Bars Leak Tablets

The tablets were added at the factory to all GM cars from the ’90s…


 
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Zerex G-05 coolant, and add two Bars Leak Tablets

The tablets were added at the factory to all GM cars from the ’90s…

That's untrue, 4500, 4900, Northstar & Very early LS1 engines are the only ones I've seen need tablets while under warranty.

The bulk of GM engines of the time which were 2.2L , 3100, 3400, 3800, 4.3L, 5.0L, 5.7L & 7.4L never required tablets.
 
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For heaven sakes don't put the tablets in it!

G05 is fine or Peak Global. 90s GM + Dexcool = trouble. I was a mechanic in that era and I made many 100s of thousands of dollars on GM and Dexcool..... maybe I'll never get over that distrust. Sludge us everything! Not just the guys who added something other than Dex. They freaken sludged from the factory! Open expansion tanks like the one you pic you posted of your 92. Pressurized tanks are known as degassing tanks and have the pressure cap on them instead of the radiator.
 
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Dexcool? Just don’t let it run low & get air in the system, or get to where it doesn’t pull coolant in from the expansion tank while cooling (as in radiator should be & stay COMPLETELY full when stone cold)-or you’ll find out where Dexcool’s rusty sludge comes from! Hint-it’s NOT always caused by mixing coolant types, and it only happens in cast iron engines!
 
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Prestone Cor-Guard(sebacate and 2-EHA along with phosphate), Toyota red(benzoate and phosphate) or G-05(benzoate, borate and silicate) would be my picks.
 
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Dexcool? Just don’t let it run low & get air in the system, or get to where it doesn’t pull coolant in from the expansion tank while cooling (as in radiator should be & stay COMPLETELY full when stone cold)-or you’ll find out where Dexcool’s rusty sludge comes from! Hint-it’s NOT always caused by mixing coolant types, and it only happens in cast iron engines!
Yes he did...This makes absolutely no sense
 
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Yes he did...This makes absolutely no sense
That's the thing about "myths"... they tend to stay that way unless it happens to you, or witness something for yourself... No Dex-Crap for me...

With all the other options out there... ??? Makes no sense...but??? Choice is a choice.
 
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