Dexcool Question
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Joined: Sep 2013
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Dexcool Question
I'm having my coolant changed tomorrow. The mechanic said he would put in a mixture of 50% Dexcool and 50% water.
Does this mixture sound right? I live in Southern California so it doesn't get cold enough to freeze.
I have had the car stored for a long time and I'm embarrassed to admit I don't think the coolant has ever been replaced (the car is a 2002). I hope I didn't screw anything up by waiting so long to change it.
Does this mixture sound right? I live in Southern California so it doesn't get cold enough to freeze.
I have had the car stored for a long time and I'm embarrassed to admit I don't think the coolant has ever been replaced (the car is a 2002). I hope I didn't screw anything up by waiting so long to change it.
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
I'm having my coolant changed tomorrow. The mechanic said he would put in a mixture of 50% Dexcool and 50% water.
Does this mixture sound right? I live in Southern California so it doesn't get cold enough to freeze.
I have had the car stored for a long time and I'm embarrassed to admit I don't think the coolant has ever been replaced (the car is a 2002). I hope I didn't screw anything up by waiting so long to change it.
Does this mixture sound right? I live in Southern California so it doesn't get cold enough to freeze.
I have had the car stored for a long time and I'm embarrassed to admit I don't think the coolant has ever been replaced (the car is a 2002). I hope I didn't screw anything up by waiting so long to change it.
Instructor
Joined: Jan 2014
Posts: 119
Likes: 1
From: Kentucky
Only after you have completely flushed ALL traces of the Dex-Cool from the cooling system. If you leave traces of the Dex-Cool then you WILL have the same problem again once you add the "green" stuff. Many if not most non-Dex-Cool coolants are NOT compatible with Dex-Cool. 
I agree 100%
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From: Staten Island NY
Melting Slicks
Joined: Jul 2006
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From: Silver Spring MD
Flush with a hose and tap water with engine running
I flushed the whole system with a garden hose connected to a heater hose after first draining the system. Kept the radiator petcock open and ran the engine. Did this until the water coming out any hole was clear.
Had to close the radiator petcock and let the car fill and come up to temp to open the thermostat and then more coolant will drain from the block. After about 20 minutes running the hose and draining with engine running and clear water coming out shut off engine and let as much water drain as possible. Did remove the gas bottle to do this and tried cleaning as much gunk out of it as possible.
Filled with about 7 quarts of full strength Dexcool and topped off with tap water. Some of the flushing tap water will stay in the system so you add the full strength Dexcool and them add more water. Have NEVER had to use distilled water as the water supply in every place I have lived is not so harsh as to cause a lot of corrosion in the system.
First time I did this the Dexcool mixture was really murky and brown. Next time about 40K later the coolant looked normal. Don't believe the 5 year 100000 mile stuff. 5 years might be OK but not 100K.
Had to close the radiator petcock and let the car fill and come up to temp to open the thermostat and then more coolant will drain from the block. After about 20 minutes running the hose and draining with engine running and clear water coming out shut off engine and let as much water drain as possible. Did remove the gas bottle to do this and tried cleaning as much gunk out of it as possible.
Filled with about 7 quarts of full strength Dexcool and topped off with tap water. Some of the flushing tap water will stay in the system so you add the full strength Dexcool and them add more water. Have NEVER had to use distilled water as the water supply in every place I have lived is not so harsh as to cause a lot of corrosion in the system.
First time I did this the Dexcool mixture was really murky and brown. Next time about 40K later the coolant looked normal. Don't believe the 5 year 100000 mile stuff. 5 years might be OK but not 100K.
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St. Jude Donor '12-'13-'14
I use Dexcool in my 2002 Vette and the 1998 WS6 and have never had an issue with it, When it comes time to change them Dexcool will be going back in them. I would say that most of the people that have issues with Dexcool was self inflicted. We also have a 2002 Tahoe with Dexcool, Again no issues.
Melting Slicks
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From: Pittsburgh PA
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50/50 is the recommended mixture.
Melting Slicks
Joined: Nov 2008
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From: Edmonton Alberta, Canada
Drifting
Joined: Dec 2009
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From: Boise Idaho
Only after you have completely flushed ALL traces of the Dex-Cool from the cooling system. If you leave traces of the Dex-Cool then you WILL have the same problem again once you add the "green" stuff. Many if not most non-Dex-Cool coolants are NOT compatible with Dex-Cool.
I even replaced over flow tank, thermostate and T stat housing.
There can be no contamination.
Never put green over orange.
Melting Slicks
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From: It's true money can't buy happiness, but it is more comfortable crying in a Corvette than on a bicyc
St. Jude Donor '13
Go read your owners manual. Green is perfectly fine. They say to change it every two years if I remember correctly. Doesn't matter if I run orange, green, or blue, although I didn't like the blue either, they all get changed every 2 or 3 years so it doesn't matter.
Racer
Joined: Mar 2010
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From: Brockton MA