Which is better: Dexcool or green stuff
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 6,252
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From: Silicon Valley Kalifornia
Which is better: Dexcool or green stuff
Which is better? Prestone has the Dexcool equivalent and the green glycol stuff. Which one should have better heat transfer properties?
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: Which is better: Dexcool or green stuff (GRX)
Cooling properties are exactly the same, both are ethelyne / glycol based. Difference is the additives.
GM issued a TSB on this and does not recommend using DexCool in older engines.
GM issued a TSB on this and does not recommend using DexCool in older engines.
Race Director
Joined: May 2001
Posts: 14,165
Likes: 9
Re: Which is better: Dexcool or green stuff (GRX)
I use DEX-COOL in mine. I flushed my block and radiator thouroughly to be sure that ALL the old coolant was gone. Why do I use it? It doesn't cool any better, but it does last longer and it looks a lot cooler.
There could be some issues on water pump seals and such, but I replaced my water pump with an electric unit at the same time so that is not really an issue.
If you really want your motor to run cool, just use water. You just a few problems to keep in mind. Obviously it will freeze, it will also boil quicker if you do manage to get it that hot. Also it has no corrosion protection, etc.
When I first did my cam change, etc I just filled it with water. My main priority was to get the motor running, not worry so much about the cooling system. It still had some anti-freeze in the block, so it was probably something like a 90%-10% mix, it looked like water with a slight green tint. Anyway with the help of my electric water pump I flushed the block and radiator for a long time until I got only clean water. I also flushed out the overflow tank.
I then drained the radiator only, then I filled it with DEX-COOL until it was full. Conviently enough this works out to be VERY close to the proper ratio. I then circulated the water with my water pump to let it mix well. I then took it for a test drive, and for all of my efforts I get a motor that runs about 5-10 degrees warmer than it did on plain water, proving that water was a better coolant. Regardless I was not going to run straight water forever, it's just dangerous for a daily driver.
Also note, I tried to do the same thing on a friend's Camaro. He didn't have the electric water pump so we were unable to flush his block as well. Now his bright clean Dex-Cool is kinda ugly and brown. Mine is still as bright as when I first put it in.
There could be some issues on water pump seals and such, but I replaced my water pump with an electric unit at the same time so that is not really an issue.
If you really want your motor to run cool, just use water. You just a few problems to keep in mind. Obviously it will freeze, it will also boil quicker if you do manage to get it that hot. Also it has no corrosion protection, etc.
When I first did my cam change, etc I just filled it with water. My main priority was to get the motor running, not worry so much about the cooling system. It still had some anti-freeze in the block, so it was probably something like a 90%-10% mix, it looked like water with a slight green tint. Anyway with the help of my electric water pump I flushed the block and radiator for a long time until I got only clean water. I also flushed out the overflow tank.
I then drained the radiator only, then I filled it with DEX-COOL until it was full. Conviently enough this works out to be VERY close to the proper ratio. I then circulated the water with my water pump to let it mix well. I then took it for a test drive, and for all of my efforts I get a motor that runs about 5-10 degrees warmer than it did on plain water, proving that water was a better coolant. Regardless I was not going to run straight water forever, it's just dangerous for a daily driver.
Also note, I tried to do the same thing on a friend's Camaro. He didn't have the electric water pump so we were unable to flush his block as well. Now his bright clean Dex-Cool is kinda ugly and brown. Mine is still as bright as when I first put it in.
