Dexcool Bad?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Safety Car
Joined: Oct 1999
Posts: 4,101
Likes: 10
From: NorCal
My 2 cents
Based upon too many years of grief, here goes.
The Green stuff was fine if you changed it regularly, typically anually. If not, it went acidic and caused problems, especially with alloy.
Then came DexCool, the magic bullet. Great stuff, but didn't live up to it's '5 year' or 'lifetime' claims. Turned to jelly or worse if left alone, and got a real bad name. Again, it was fine if you changed it regularly, like every other year, and it didn't eat up alloy.
Now we come to the 'yellow' stuff. First used by Mercedes, then Ford and most Asian imports. Seems to have solved the Gel problem and lasts 'forever'...
I service a fleet of 800 units. We change our fluids regularly and have near zero problems. We use all three, based on manufacturer's recomendations, but don't follow their intervals. Coolant gets changed every 30K or two years, no matter what, except the few 'green' ones we have left. Those are annuals changes.
The key is, why save a few bucks and risk your cars life? I still use 'green' in the old cars I own, and change it twice a year. Piece of cake, and no problems.
hans
The Green stuff was fine if you changed it regularly, typically anually. If not, it went acidic and caused problems, especially with alloy.
Then came DexCool, the magic bullet. Great stuff, but didn't live up to it's '5 year' or 'lifetime' claims. Turned to jelly or worse if left alone, and got a real bad name. Again, it was fine if you changed it regularly, like every other year, and it didn't eat up alloy.
Now we come to the 'yellow' stuff. First used by Mercedes, then Ford and most Asian imports. Seems to have solved the Gel problem and lasts 'forever'...
I service a fleet of 800 units. We change our fluids regularly and have near zero problems. We use all three, based on manufacturer's recomendations, but don't follow their intervals. Coolant gets changed every 30K or two years, no matter what, except the few 'green' ones we have left. Those are annuals changes.
The key is, why save a few bucks and risk your cars life? I still use 'green' in the old cars I own, and change it twice a year. Piece of cake, and no problems.
hans
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Based upon too many years of grief, here goes.
The Green stuff was fine if you changed it regularly, typically anually. If not, it went acidic and caused problems, especially with alloy.
Then came DexCool, the magic bullet. Great stuff, but didn't live up to it's '5 year' or 'lifetime' claims. Turned to jelly or worse if left alone, and got a real bad name. Again, it was fine if you changed it regularly, like every other year, and it didn't eat up alloy.
Now we come to the 'yellow' stuff. First used by Mercedes, then Ford and most Asian imports. Seems to have solved the Gel problem and lasts 'forever'...
I service a fleet of 800 units. We change our fluids regularly and have near zero problems. We use all three, based on manufacturer's recomendations, but don't follow their intervals. Coolant gets changed every 30K or two years, no matter what, except the few 'green' ones we have left. Those are annuals changes.
The key is, why save a few bucks and risk your cars life? I still use 'green' in the old cars I own, and change it twice a year. Piece of cake, and no problems.
hans
The Green stuff was fine if you changed it regularly, typically anually. If not, it went acidic and caused problems, especially with alloy.
Then came DexCool, the magic bullet. Great stuff, but didn't live up to it's '5 year' or 'lifetime' claims. Turned to jelly or worse if left alone, and got a real bad name. Again, it was fine if you changed it regularly, like every other year, and it didn't eat up alloy.
Now we come to the 'yellow' stuff. First used by Mercedes, then Ford and most Asian imports. Seems to have solved the Gel problem and lasts 'forever'...
I service a fleet of 800 units. We change our fluids regularly and have near zero problems. We use all three, based on manufacturer's recomendations, but don't follow their intervals. Coolant gets changed every 30K or two years, no matter what, except the few 'green' ones we have left. Those are annuals changes.
The key is, why save a few bucks and risk your cars life? I still use 'green' in the old cars I own, and change it twice a year. Piece of cake, and no problems.
hans
I change annually no matter what color.
Drifting
Joined: Aug 2004
Posts: 1,677
Likes: 1
From: Potomac Falls VA
Melting Slicks
Joined: May 1999
Posts: 2,897
Likes: 0
From: Moon Township PA
I think that there is enough information to say that if you don't mind flushing your system annually then the Prestone-type green stuff is adequate. By that I mean, draining the radiator AND the block by pulling the block drains. I do this in the summer time, knowing I am going to get soaked since I have to be on my back, under the engine to do this.
Like others, I am getting old enough that crawling under the jacked up car to drain my coolant is a PITA. Plus, I have four cars. So, I switched to Zerex and go with a two year cycle, and, like always, I use distilled water.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
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Drifting
Joined: Aug 2004
Posts: 1,677
Likes: 1
From: Potomac Falls VA
Interesting response from Valvoline (makers of Zerex) on dexcool
"Keep in mind that Dexcool is made by several blenders and Valvoline did not make the original version that GM used. Our formulation is 100% tested not to cause the issues you mentioned. Valvoline still recommends our version of Dexcool for applications that need this formulation to provide the correct corrosion protection for certain system metals."
"Keep in mind that Dexcool is made by several blenders and Valvoline did not make the original version that GM used. Our formulation is 100% tested not to cause the issues you mentioned. Valvoline still recommends our version of Dexcool for applications that need this formulation to provide the correct corrosion protection for certain system metals."
Drifting
Joined: May 2005
Posts: 1,629
Likes: 4
From: Somers CT
That's a little extreme and I don't think it's warrented. Backflushing the system until it's free of antifreeze as you stated should do the trick.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Burning Brakes
Joined: Feb 2005
Posts: 1,235
Likes: 0
From: Mesa AZ
if you live in a hot climate you could save yourself a lot of trouble and just run straight distilled water. i have a small leak on my water neck that i can't get sealed to save my life ( i think the intake casting is cracked ) and i'm running water with no cooling problems at all . antifreeze only raises the boiling point and my car never goes over 180 so it never gets close to boiling even water.
Melting Slicks
Joined: May 1999
Posts: 2,897
Likes: 0
From: Moon Township PA
if you live in a hot climate you could save yourself a lot of trouble and just run straight distilled water. i have a small leak on my water neck that i can't get sealed to save my life ( i think the intake casting is cracked ) and i'm running water with no cooling problems at all . antifreeze only raises the boiling point and my car never goes over 180 so it never gets close to boiling even water.
These products prevent corrosion/rust internally and lubricate rotating parts like your water pump. Running pure water might not hurt in the short term but is definetly a recipe for disaster in the long term. In addition, iirc, running distilled water without coolant is bad. Don't remember why though. I THINK it leaches chemicals out of the block to reach a stabile state - homeostasis (any chemists out there? does that sound right). Topgunn, the reason for draining the engine at the block drains is that there will be at least a quart or two of trapped water/coolant low in the block that never gets flushed. If you remember from basic physics, water will find the easiest path to flow and will most likely never root out the crap that finds its way down deep into the lower areas of the block.
Drifting
Joined: May 2005
Posts: 1,629
Likes: 4
From: Somers CT
).
Topgunn, the reason for draining the engine at the block drains is that there will be at least a quart or two of trapped water/coolant low in the block that never gets flushed. If you remember from basic physics, water will find the easiest path to flow and will most likely never root out the crap that finds its way down deep into the lower areas of the block.
Topgunn, the reason for draining the engine at the block drains is that there will be at least a quart or two of trapped water/coolant low in the block that never gets flushed. If you remember from basic physics, water will find the easiest path to flow and will most likely never root out the crap that finds its way down deep into the lower areas of the block.
Hi Gary,
No problem, I agree on the block drains but the statement that was made was "pulling the water jacket plugs" or what some might call "freeze plugs". I maintain pulling those and replacing them would seem unwarranted for the purpose of flushing the coolant system.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Hi Gary,
No problem, I agree on the block drains but the statement that was made was "pulling the water jacket plugs" or what some might call "freeze plugs". I maintain pulling those and replacing them would seem unwarranted for the purpose of flushing the coolant system.
No problem, I agree on the block drains but the statement that was made was "pulling the water jacket plugs" or what some might call "freeze plugs". I maintain pulling those and replacing them would seem unwarranted for the purpose of flushing the coolant system.
I didn't mean these...
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
if you live in a hot climate you could save yourself a lot of trouble and just run straight distilled water. i have a small leak on my water neck that i can't get sealed to save my life ( i think the intake casting is cracked ) and i'm running water with no cooling problems at all . antifreeze only raises the boiling point and my car never goes over 180 so it never gets close to boiling even water.
Anti-Freeze, while it's main purpose is to stop freezing, also contains chemicals that prevent corrosion that would be otherwise caused by using staight water. While I agree that the anti-freeze may decrease the boiling point, it isn't much. If you are really woorried about lowering the boiling point, than use a 20/80 mix (20 antifreeze and 80 water) this will limit the lowered boiing point to a mimimum, while still having the chemicals required to prevent corrosion.
On another note... if your car is getting close to the boiling point with a 50/50 mix, than you have another cooling problem that needs to be addressed.