ALERT: DexCool Coolant! READ!
Drifting
Joined: Feb 2003
Posts: 1,778
Likes: 1
From: Myakka City Fl
It's OK
OGC5
Tech Contributor
Joined: Dec 2006
Posts: 10,962
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From: Van Buren Arkansas
Wounded Warrior Escort '11
I'm on my 2nd fill of Dexcool in my '99. At over 300K miles, there has been no problems with it. I'll probably change it again in the spring just for preventive maintenance.
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
DEXCOOL has changed since the "problems" that some experienced. There is no problem with DEXCOOL in aluminum LSx motors. The problem was with DEXCOOL and the GM added tablets and probably poor coolant system maintenance (primarily complained about in iron block/aluminum head motors LT1/LT4).
But it's your car to do with as you please!
http://forums.corvetteforum.com/show....php?t=1882401
But it's your car to do with as you please!
http://forums.corvetteforum.com/show....php?t=1882401
Last edited by hotwheels57; Dec 13, 2007 at 11:39 AM.
Le Mans Master
Joined: Feb 2002
Posts: 6,937
Likes: 21
From: Waldorf MD
This is OLD News, the main problem with Dexcool is when you get air in the system (as in a leak), then it turns to a muddy brown mess.
The culprit was actually cheap GM gaskets, which failed and allowed air in the system, without people taking corrective action on this problem, the mess developed.
I have 109,000 miles on my 1998 and have just completed the second drain and fill with Dexcool. It looks great. I have never flushed the system because the coolant looks so good and the Shop Manual says a flush is not needed. Note that I do drain out all but 2 quarts of coolant when I drain it.
I had even converted several of my previous cars to Dexcool, without any problems.
I will continue using Dexcool, it cools better and protects better than any other coolant, and a five year service interval is GREAT !
The culprit was actually cheap GM gaskets, which failed and allowed air in the system, without people taking corrective action on this problem, the mess developed.
I have 109,000 miles on my 1998 and have just completed the second drain and fill with Dexcool. It looks great. I have never flushed the system because the coolant looks so good and the Shop Manual says a flush is not needed. Note that I do drain out all but 2 quarts of coolant when I drain it.
I had even converted several of my previous cars to Dexcool, without any problems.
I will continue using Dexcool, it cools better and protects better than any other coolant, and a five year service interval is GREAT !
Last edited by Oldvetter; Dec 13, 2007 at 03:11 PM.
Burning Brakes
Joined: Jul 2006
Posts: 968
Likes: 12
From: Regina Sask
Dexcool is propolyene glycol based. It isn't a problem until you get air in the cooling system (gasket leaks). Then it turns into brown mud, plugging the heater core & radiator. At my shop, we use Peak Global antifreeze that is ethylene glycol based, and isn't affected by having air in the cooling system.
Russ Kemp
Russ Kemp
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Joined: Apr 2001
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From: S.W. Ohio. . . . . . NRA Life Member
Using Dexcool must caus irrepairable damage as I've had it in my car for well over 100k and the hoses/waterpump still look like new.
Those people need to blame the dealerships that're screwin em and quit looking to GM.
My personal fav quote:
"The product in vehicles coolant systems deteriorates aluminum parts in the engine," Ronald said. "The intake manifold, cylinder heads and timing chain cover are all made out of aluminum. My vehicle needs all these parts replaced."
His problems worsened. "The motor has coolant in the oil and oil in coolant," indicating that the head gasket is leaking. "This is the second time this problem has occurred."
What a tool.
Those people need to blame the dealerships that're screwin em and quit looking to GM.
My personal fav quote:
"The product in vehicles coolant systems deteriorates aluminum parts in the engine," Ronald said. "The intake manifold, cylinder heads and timing chain cover are all made out of aluminum. My vehicle needs all these parts replaced."
His problems worsened. "The motor has coolant in the oil and oil in coolant," indicating that the head gasket is leaking. "This is the second time this problem has occurred."
What a tool.
Had lawyers been around during the creation... as soon as God said "let there be water"... some lawyer would of filed a class-action lawsuit about the existence of water... with all sorts of "data"
to justify the legal undertaking.Like you did; somethmes we need to read further... than what we are offered during internet searches.
Le Mans Master
Joined: Dec 2001
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From: Winchester TN
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Hi CharlieB1979 -
DEXCOOL does not corrode aluminum in my experience. I ran my 1998 Lumina 176k miles using DEXCOOL and experienced no coolant related issues whatsoever.
In regards to mixing the coolants - they are compatible for the purpose of cooling, but it is my understanding that if you put any of the older formulation into the mix, it takes away the longevity of the DEX - in other words, you have to change it out annually instead of every 5 years.
best regards -
mqqn
DEXCOOL does not corrode aluminum in my experience. I ran my 1998 Lumina 176k miles using DEXCOOL and experienced no coolant related issues whatsoever.
In regards to mixing the coolants - they are compatible for the purpose of cooling, but it is my understanding that if you put any of the older formulation into the mix, it takes away the longevity of the DEX - in other words, you have to change it out annually instead of every 5 years.
best regards -
mqqn
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Changed my coolant at the four year mark and everything looked like new. Put Dexcool back in - no reason not to IMO.
Racer
Joined: Nov 2007
Posts: 257
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I'm glad this thread came up...
I'm a new vette owner..please inform me on a few things guys/gals.
A. the Dex-Coolant..50/50...can i just fill up the coolant with 100% Dex Cool? or do I HAVE to mix it with water?
B. How often should the vehicle be flushed of "old" coolant?
I'm a new vette owner..please inform me on a few things guys/gals.
A. the Dex-Coolant..50/50...can i just fill up the coolant with 100% Dex Cool? or do I HAVE to mix it with water?
B. How often should the vehicle be flushed of "old" coolant?
Drifting
Joined: Feb 2003
Posts: 1,778
Likes: 1
From: Myakka City Fl
100% is a No
I'm glad this thread came up...
I'm a new vette owner..please inform me on a few things guys/gals.
A. the Dex-Coolant..50/50...can i just fill up the coolant with 100% Dex Cool? or do I HAVE to mix it with water?
B. How often should the vehicle be flushed of "old" coolant?
I'm a new vette owner..please inform me on a few things guys/gals.
A. the Dex-Coolant..50/50...can i just fill up the coolant with 100% Dex Cool? or do I HAVE to mix it with water?
B. How often should the vehicle be flushed of "old" coolant?
B. Every two years in my opinion just for insurance. The Coolant lasts a long time but the anti corrosion stuff gets weak.
OGC5
Last edited by OGC5; Dec 13, 2007 at 07:01 PM. Reason: word
Instructor
Joined: Jan 2006
Posts: 128
Likes: 0
Don't mix the green and DexCool. Use DexCool and distilled water in a 50-50 mix.
I don't know about DexCool...
I'm second owner on my '97 Eldorado, it was 2 years old with 30,000 miles when I bought it. I've maintained the cooling system while I've had the car. Anyway a year ago I had to TimeSert the Northstar block in my car at 91,449 miles. The headbolts in the rear head pulled right out of the block!
Now...it is said that old, worn out DexCool causes this by corroding the headgaskets and seeping down into the headbolt holes in the block corroding the threaded aluminum and allowing the headbolts to pull out.
I could find NO EVIDENCE ANYWHERE of any corrosion whatsoever on those headgaskets. I'm of the opinion that the problem may lie with a poorly made headgasket of in-appropriate material.
Anyway my Eldo now runs better than it has in years and I'm saving my loot to buy a C5 later this year.
I don't know about DexCool...
I'm second owner on my '97 Eldorado, it was 2 years old with 30,000 miles when I bought it. I've maintained the cooling system while I've had the car. Anyway a year ago I had to TimeSert the Northstar block in my car at 91,449 miles. The headbolts in the rear head pulled right out of the block!
Now...it is said that old, worn out DexCool causes this by corroding the headgaskets and seeping down into the headbolt holes in the block corroding the threaded aluminum and allowing the headbolts to pull out.
I could find NO EVIDENCE ANYWHERE of any corrosion whatsoever on those headgaskets. I'm of the opinion that the problem may lie with a poorly made headgasket of in-appropriate material.
Anyway my Eldo now runs better than it has in years and I'm saving my loot to buy a C5 later this year.
Melting Slicks
Joined: Sep 2005
Posts: 2,625
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From: Rhode Island
I have to cast my vote for Dexcool. My car is 10 years old and when I did my heads/ cam, I inspected it thoroughly. I have to say it looks like brand new inside and Dexcool has been in it since day one.
Drifting
Joined: Feb 2003
Posts: 1,778
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From: Myakka City Fl
I thought so also but mabye not
Dexcool is propolyene glycol based. It isn't a problem until you get air in the cooling system (gasket leaks). Then it turns into brown mud, plugging the heater core & radiator. At my shop, we use Peak Global antifreeze that is ethylene glycol based, and isn't affected by having air in the cooling system.
Russ Kemp
Russ Kemp
OGC5
OK we have beat that horse enough!
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I now have a 50/50 mix of Dex and distilled water and will continue using Dex.
Le Mans Master
Joined: Dec 2006
Posts: 7,251
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From: Phoenix Arizona
Horse Pucky! Lawyers continue to collect names for potential class action lawsuits from people claiming Dex-Cool damaged their car.
Prestone and other suppliers offer a Dex-cool which is an organic based mixture in addition to the Propolyene Glycol based stuff. All have anti corrosion additives and can be mixed together although not recommended. Prestone and GM have experienced engineers and I doubt that they would fill the Corvette at the factory with a defective mix. They do however use Kentucky Tap water to mix with the coolant so I drain and refill with distilled water and 50% Dex. Darn stuff is always clean although I do refill every two years as I am a typical Obsessive Corvette owner. The average driver idiot out there probably does not even know where the Radiator cap is located.My 2 cents.
OGC5
Prestone and other suppliers offer a Dex-cool which is an organic based mixture in addition to the Propolyene Glycol based stuff. All have anti corrosion additives and can be mixed together although not recommended. Prestone and GM have experienced engineers and I doubt that they would fill the Corvette at the factory with a defective mix. They do however use Kentucky Tap water to mix with the coolant so I drain and refill with distilled water and 50% Dex. Darn stuff is always clean although I do refill every two years as I am a typical Obsessive Corvette owner. The average driver idiot out there probably does not even know where the Radiator cap is located.My 2 cents.
OGC5
all i have is an expansion tank cap 
hehe
