thanks!
Radiator fluid question
Tech Contributor
Joined: Oct 1999
Posts: 41,037
Likes: 9,799
From: Charlotte, NC (formerly Endicott, NY)
NO!!! DO NOT LISTEN TO THAT PERSON!!! Dexcool works fine in the Corvette engine and is a very good coolant. I have been running it in GM cars since I bought my 97 Vette 12 years ago. I run the complete 5 years with the coolant and one car has even gone through two 5 year changes. No problems with any of the cars. Dexcool works especially well with the Corvette's aluminum engine. If you change to the green stuff you could have problems and you will definitely be on a 2 year change cycle.
Bill
Bill
Le Mans Master
Joined: Sep 2003
Posts: 8,847
Likes: 795
From: Longview Texas
I have not had any problems, but I hate to let any fluid go 5 years, so I use Dexcool but still change my coolant every 2-3 years.
The second reason I change it more often is that I do not do a complete flush. I just drain the 2 gallons I can from the radiator, and refill with a 50/50 mix.
The second reason I change it more often is that I do not do a complete flush. I just drain the 2 gallons I can from the radiator, and refill with a 50/50 mix.
Tech Contributor
Joined: Jan 2007
Posts: 19,398
Likes: 1,139
From: Dyer, IN
Drifting
Joined: Jan 2005
Posts: 1,724
Likes: 0
From: Oil Country
What about the extended life green coolant? I just stood up my rad from its previous laid down position and replaced the hoses etc. I filled the system with "Peak pre mixed 50/50 extended life coolant". It says that it is good for 5 years or 240,000kms (probably around 140,000 miles). It had the same certification as the Prestone "dex-cool" coolant. Is there a problem using that?
Tech Contributor
Joined: Jan 2007
Posts: 19,398
Likes: 1,139
From: Dyer, IN
What about the extended life green coolant? I just stood up my rad from its previous laid down position and replaced the hoses etc. I filled the system with "Peak pre mixed 50/50 extended life coolant". It says that it is good for 5 years or 240,000kms (probably around 140,000 miles). It had the same certification as the Prestone "dex-cool" coolant. Is there a problem using that?
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Nope. That's the hood seal. 
Racer
Joined: Apr 2007
Posts: 330
Likes: 33
From: Milwaukee WI
I called a GM dealership and they said they used the Prestone extended life (yellow stuff). I called Prestone and asked which was better: their Dexcool or the yellow stuff, and they pretty much said they are the same thing.
Team Owner
Joined: May 2001
Posts: 36,836
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
The Dex-Cool formulated versions are propylene glycol and are silicate free. The "regular" version is ethylene glycol and has been around for years. The ethylene versions are OK overall, but need more frequent changing/flushing.
Le Mans Master
Joined: Sep 2003
Posts: 8,847
Likes: 795
From: Longview Texas
I would still make sure I used a brand that was GM Dexcool approved, and not just Dexcool compatible or extended life.
Prestone is definitely an authorized manufacturer of Dexcool, but not sure about other brands like PEAK. I think I would stay with Prestone since Texaco Havoline is not readily available.
Since Prestone is an approved manufacturer, there is a good chance that even the Dexcool you buy at the dealer in the GM bottle was made by Prestone.
Dexcool is formulated to eliminate silicates and other chemicals that prevent corrosion, but are harder on water pump seals and other parts of the engine, so I would not go back to the green stuff.
Prestone is definitely an authorized manufacturer of Dexcool, but not sure about other brands like PEAK. I think I would stay with Prestone since Texaco Havoline is not readily available.
Since Prestone is an approved manufacturer, there is a good chance that even the Dexcool you buy at the dealer in the GM bottle was made by Prestone.
Dexcool is formulated to eliminate silicates and other chemicals that prevent corrosion, but are harder on water pump seals and other parts of the engine, so I would not go back to the green stuff.
Safety Car
Joined: Oct 2003
Posts: 3,699
Likes: 16
From: Sun City- Menifee Calif.
Not sure if this applies, but a few years back I had a 96 Dodge truck That had the dexcool in it. At around 100,000 miles & 4 years I flushed it out & replaced with the green coolant. Within a few days it started overheating for no apparent reason . No leaks. replaced thermostat, Never figured it out. Traded it in on a deisel Dodge because I drove long miles every day for work. I later found out that you should never use the green stuff in a car that has Dexcool. Some kind of a reaction that damages the Radiator or maybe the head gasket. Never really found out what. But now I use only the same coolant that each vehicle started with.
