Which extended life coolant for a '95 Buick Skylark?

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Currently has the traditional green stuff and I will be doing a complete flush so I can start from scratch. Will not be using the same old school green as I want something with longer life. This 1995 was a split year with the early cars getting the green coolant before changing to Dexcool later in the year. Any reason I can’t switch it to Dexcool? Or are there any green color long life coolants that would work? Like the green Asian formula POAT from Peak for example? Another option may be something like Prestone Platinum All Vehicle coolant. And do I still need to add those sealant tablets with these modern coolants?
 
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Some GM vehicles that had Dexcool as factory fill in the early days had gasket issues. GM changed gasket materials on some later vehicles.
I could be wrong.
 

atikovi

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Some GM vehicles that had Dexcool as factory fill in the early days had gasket issues. GM changed gasket materials on some later vehicles.
I could be wrong.
Yes but that was determined to be a gasket issue, not so much a Dexcool problem. Cars with green coolant also had those issues.
 
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Currently has the traditional green stuff and I will be doing a complete flush so I can start from scratch. Will not be using the same old school green as I want something with longer life. This 1995 was a split year with the early cars getting the green coolant before changing to Dexcool later in the year. Any reason I can’t switch it to Dexcool? Or are there any green color long life coolants that would work? Like the green Asian formula POAT from Peak for example? Another option may be something like Prestone Platinum All Vehicle coolant. And do I still need to add those sealant tablets with these modern coolants?
Your call, but if this vehicle has had Green Coolant for 22 years I would just stick with the old stuff and change it every 2 years. I would also use distilled water, I do this on an older car, basically I just take off the lower radiator hose, drain the coolant and then add new coolant with distilled water.

I have heard of people having issues when they go from green coolant to another type of coolant.
 

atikovi

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Third drain and water refill. Still muddy or is that from those tablets?

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I think I'd do a 4th water flush still looks muddy to me. After that I'd go with which ever universal AMAM flavor you prefer. I've got Prestone universal in a GM of that vintage with no issues after 3+ years. I did put in the improved intake manifold gaskets (4.3 v6) prior to the coolant change.
 
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Keep flushing with tap water until it's clear. Then flush a few more times with distilled. Then add X amount of concentrate. You should really know the coolant capacity beforehand. Then add 50/50 and test.
 
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I'm not finished until it comes out clear.

Here is how to get this thing clear, undo the thermostat housing and take out the thermostat, put the thermostat housing back on. Disconnect the upper radiator hose, and then attach an additional hose and aim it into a 5 gallon bucket. Start the car and keep adding water until it becomes clear. I would run the heater while you are doing this, I did this on a 97 Monte Carlo with a 3.1 V6, I think that car held 13 quarts of coolant, I ending up putting 20 quarts of water into the system before it came clear.

If this car does not make good heat, then I would replace the heater core. I have also seen videos where guys take off the lower radiator hose and and then take the thermostat off and flush it from the intake manifold. This drain and fill in your situation is a waste of time.
 
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american green antifreeze in any application = no

Why not? That's what the OP's car came with from the factory :unsure:

Green silicate coolant has been in use since 1920 with no problems. The garbage GM switched to the following year is when the problems came :sneaky:

Peak 10x is a good universal coolant with no problems, if you don't like silicate for some reason.
 

atikovi

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Why not? That's what the OP's car came with from the factory :unsure:

Green silicate coolant has been in use since 1920 with no problems. The garbage GM switched to the following year is when the problems came :sneaky:

Peak 10x is a good universal coolant with no problems, if you don't like silicate for some reason.
That's no excuse. Would you use SA grade motor oil from the Model A era in your car today when modern synthetics are superior? Leaning towards the Prestone Platinum available at Walmart or Dexcool which I already have on hand.
 
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That's no excuse. Would you use SA grade motor oil from the Model A era in your car today when modern synthetics are superior? Leaning towards the Prestone Platinum available at Walmart or Dexcool which I already have on hand.

except oil actually did/does have problems. SA oil couldn't keep up with newer engines. Deposits, sludge, etc. New oil can be used in older engines with no problem. For your Model A example, using modern synthetic oil in a Model A will not cause any problems at all, but using Dexcool or most other modern coolants will!

New coolant often can't be used in some older cars. GM (and people who bought their cars new in the late 90s) found out the hard way. Your 3100 is a prime example of this: it wasn't designed for Dexcool and it turned out to not be backwards-compatible. Your car came with 1920 green coolant but did not come with SA oil.

The oil analogy doesn't hold up with coolant. Though there are some universal coolants that are backwards-compatible with your car (Peak 10x, PGL, G05, etc), Dexcool definitely isn't.

If your coolant choice is between Prestone Platinum and Dexcool that you already have, there is no point in buying Prestone because it's a dexclone and too similar to what you already have.
 

atikovi

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New coolant often can't be used in some older cars. GM (and people who bought their cars new in the late 90s) found out the hard way. Your 3100 is a prime example of this: it wasn't designed for Dexcool and it turned out to not be backwards-compatible.
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.
 
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