dex cool antifreeze switch or not

[snake123]

I just purchased a car with dex cool , a Buick lesabre , used 30,ooo miles on it runs great , I notice it only uses dex cool antifreeze , ,so when I did some research , wow wee, they say it runs seals gaskets metal plastic , now if this is all true should I switch the antifreezes to regular green preston or leave well enough alone?

 

[gfh77665]

Leave it alone. I know about all the internet horror stories, but in reality, I have owned GM products for 15-20 years using only Dexcool, and have had no problems.

 

[Kuato]

One thing I've seen on Dexcool over and over is that you should not let the level get low as that is what causes the problems.

All said and done it's your vehicle so you could do a flush and refill with different coolant if it is a concern.

 

[Sayjac]

No idea what year, but if it's had Dex in it for some time and has the less than compatible ('plastic type') GM oem gaskets, likely already done it's deed if it's going to. Changing to something else likely make little or no difference. So just stick with Dexcool, and go from there.

And be careful what you call regular green Prestone. Prestone All Makes Models is yellowish to green depending on how viewed. Prestone is just a Dexclone and also contains 2eha like name brand Dex, which is the plasticizer ingredient known to attack/weaken some gasket and seal materials. So, nothing gained by using it.

 

[hatt]

If Dex was fundamentally bad I doubt Ford would have started using it after all these years.

 

[eljefino]

Originally Posted By: Sayjac

And be careful what you call regular green Prestone. Prestone All Makes Models is yellowish to green depending on how viewed. Prestone is just a Dexclone and also contains 2eha like name brand Dex, which is the plasticizer ingredient known to attack/weaken some gasket and seal materials. So, nothing gained by using it.


Nothing gained, nothing lost. The store brand stuff is yellowish dexcool, too, usually. (look for 5 year long life claims.) It comes down to, change it somewhat often, IMO.

That motor has some sort of coolant pipe for the heater hose that goes kablooey, beware.

 

[Kira]

C'mon snake, Include year, make, model and trim level (include engine size) in posts. "A Buick..." isn't near good enough. Is it the 3800 by chance?

RANT OVER.

The engines having problems with Dex-Cool are long gone.

The problems with Dex-Cool is when people use it in a car with a "non air-tight" system.
EXAMPLE: My sister's '99 Jeep with a mere bug flap over the coolant recovery bottle would spell disaster.
Also, never mix coolants. Dex-Cool is one which doesn't like to be mixed/contaminated.

Flushed out "Christmas Coolant" (red and green mixed) from 2 GM Saabs and replaced with clean Dex mixed 50/50 with distilled water and all is well.

Another friend had a THOROUGHLY NEGLECTED Chevy ('03 S-10) which had the rustiest coolant I've ever seen. Cleaned it up and replaced with Dex-Cool. Happy twuck

 

[Sayjac]

Quote:
... Nothing gained, nothing lost. The store brand stuff is yellowish dexcool, too, usually..

Yes, most common AFs sold as store brands also dexclones like Prestone AM/M and still make up the common type sold at AP stores and places like WM as ST brand AF.

'For me', if my vehicle called for Dexcool, that's what I'd use rather than going to a dexclone AM/M AF. Just me.

As for nothing gained or lost, just making OP aware that if the desire was/is to avoid 2eha as a gasket plasticizer, nothing gained by going to a dexclone imo. True original/conventional green, like Zerex or others, another matter.

 

[Trav]

Originally Posted By: snake123
I just purchased a car with dex cool , a Buick lesabre , used 30,ooo miles on it runs great , I notice it only uses dex cool antifreeze , ,so when I did some research , wow wee, they say it runs seals gaskets metal plastic , now if this is all true should I switch the antifreezes to regular green preston or leave well enough alone?

If its an old one then you need to think about than just the coolant, if its newer than 08 then forget it.
08 IIRC was the last revision of the lower intake gaskets for the 3800 and the aluminum frame gaskets cured them.

 

[Boss302fan]

If it is before 2008, then I would drain and fill with Dexcool on the radiator and the recovery bottle. Just make sure you keep an eye on the recovery bottle and keep it at the full max line when cool. Never want air in any of those coolant systems.

 

[bigt61]

Originally Posted By: Kuato
One thing I've seen on Dexcool over and over is that you should not let the level get low as that is what causes the problems.

All said and done it's your vehicle so you could do a flush and refill with different coolant if it is a concern.

Yeah, Dexcool is fine, just don't let it get low.

 

[callbay]

I just got a 2002 Buick Regal. 147,000 miles.

It has dex cool in it but only protected down to +15 degrees.

The low cooland light is on but the system and recovery tank seem full.

I want to do a flush and new coolant.

Will regular Wal Mart cooland be alright?

Why the add cooland light on?

Thanks a ton!

 

[Trav]

This means the coolant level in the radiator is too low to create enough vacuum when cooling to draw enough from the overflow bottle.
The coolant level sensor on these is on the pass side radiator tank about 5 inches down near the battery.
You need to top of the radiator by removing the cap when its cold.

With that many miles and an unknown history I would strongly suspect LIM gasket leakage and/or possible EGR chimney burn through of the UIM.
I replace the LIM gaskets and install a new aftermarket UIM with a metal EGR sleeve and a reduced diameter EGR chimney as preventive maintenance. This is also a good time to replace the plastic coolant elbows with new aluminum ones.

After a good flushing I use G-O5 or John Deere Coolguard for coolant. Dexcool was not the problem it was gasket material compatibility.
Even though the new gaskets addressed the compatibility issue the radiator still uses a pressure cap that can be a source of introducing a little air in the system which can cause coolant sludge issues.
For that reason I still change the coolant from Dexcool. If the engine uses a pressure tank with no radiator cap then its a non issue.

 

[callbay]

Wow. Thanks, Trav!

 

[wolf_06]

this is a funny question, why risk something important like coolant for your engine, use what the manual calls for. Period.

 

[Trav]

When the manual was written they didn't have all the failure yet. GM thought they had this fixed many times with every new revision of the gasket but it didn't fix it until many years after the initial failures started cropping up. Its that simple.

This is the problem with manuals, they are only current and correct when they are written, they don't issue any addendum to it with current information to vehicle owners although the dealers do get TSB's.

 

[Kuato]

.

 

[TmanP]

I'd use DexCool, but change it every 5 years or 150,000 miles- whichever comes FIRST! I have it in my Buick. The issue with DexCool was that people left it in too long. It's fine for its recommended interval.

 

[Trav]

Sludge was an issue on some of the older cars. I think its fair to say vehicles with a radiator cap would probably be better without dexcool and cars with a pressure bottle its safe to leave.
Its not just the time or miles its the presence of air, the sludge in the cooling system can be a real nightmare.

 

[demarpaint]

Originally Posted By: Trav
When the manual was written they didn't have all the failure yet. GM thought they had this fixed many times with every new revision of the gasket but it didn't fix it until many years after the initial failures started cropping up. Its that simple.


You mean the engineers didn't get it right, then had trouble fixing it. How could that be?