Dexcool antifreeze
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Thanks for the info. I need to do a coolant change, so this will come in handy.
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Anybody have an opinion or know which is better to use, the full strength or 50/50? I know you don't use the coolant at full strength, but does the C5 require a 50/50 mix?
Thanks
Thanks
Pro
Joined: Oct 2007
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From: Morris County, NJ
if you use the 50/50 you do not have to buy distilled water at about a buck a gallon. If I were doing a complete flush, I'd use the full strength and add distilled water. If I was just doing a drain and refill, I'd use the 50/50 already mixed stuff
Steve
Steve
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Thanks Steve.
Mark
Mark
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From: Belleville Il
Ok,,I'll ask(I know there are more out there that want to know) Just how much do we need for a flush. I can blow out the block and have the equipment to "BURP" the motor!! Just need to know how much for a full fill!!
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From: belle plaine ks
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I haven't changed it I figured if it would mess up our cars I would have seen more post about it by now. I hope its OK if not I'm sure someone will chime in.
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There is nothing wrong with Dexcool at all, It can't be beat, Just use as stated and use distilled water and it will last for years. Most that had troubles with is mis used it or used tap water. Operator error.
Burning Brakes
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From: belle plaine ks
There are just too many stories about problems related to this coolant. It may not be the direct cause of any problems, but you never hear of that many problems with the green. Do a google search of the problems related to this coolant. I believe it is a combination of factors, but I believe going to the green with a totally clear flush to distilled water in between is a better choice.
Le Mans Master
Joined: Sep 2003
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From: Longview Texas
I think most of the problems reported with Dexcool are due to improperly maintained cooling systems, where air gets in the system. I have found that it also may have something to do with the design of the cooling system. I have a Malibu, and it forms a brown film in the overflow tank no matter what I do, but on my Impala and Corvette, the Dexcool always drains out perfectly clean. The Corvette has a fully pressurized surge tank, and the Impala has a tank vented to atmosphere with the cap on the engine. The Malibu has a pressurized tank similar to the Corvette, so it is not obvious what causes the film to form.
For the ones wanting to do a complete flush, the system holds 12 quarts. When I drain mine, I get about 8 quarts out, leaving about a gallon in the block. I usually just do not let mine go over 2-3 years, and replace what I can drain.
The 50/50 premix would be great if it did not cost twice as much. The bottles I have seen cost the same as the full strength Dexcool, and you are paying for 50% water. Just buy a gallon of Dexcool and a gallon of distilled water, and make 2 gallons.
For the ones wanting to do a complete flush, the system holds 12 quarts. When I drain mine, I get about 8 quarts out, leaving about a gallon in the block. I usually just do not let mine go over 2-3 years, and replace what I can drain.
The 50/50 premix would be great if it did not cost twice as much. The bottles I have seen cost the same as the full strength Dexcool, and you are paying for 50% water. Just buy a gallon of Dexcool and a gallon of distilled water, and make 2 gallons.
Last edited by TEXHAWK0; Jan 12, 2010 at 01:54 PM.
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The chemical construction of 'DexCool' is a perfect product. BUT, the coolant MUST be changed every five years on time. Not six or eight or any other time span. ALSO, DexCool, once installed in your car, needs to be isolated from the open air. So the first thing is to do a complete and through flush and the inspect your whole cooling system, replace any possible bad hoses or leaky radiator seams, heater core, ect. That is necessary because once the DexCool coolant mixes with air, it starts to degrade. It's not like the old days where if you had a minor leak, you could just top off the expansion tank or radiator. DexCool, Once it mixes with air, it's going to be a very short path to engine trouble. And that's not GM's problem, you as the cars owner is/are responsible to once in awhile to look the car over. That includes making sure the overflow tank isn't empty, by then it's too late. And it's not like we can go back to the green stuff, it is being phased out by the EPA, who mandated the change to DexCool a number of years ago. So I don't like it either, but we have no choice.
Intermediate
Joined: Sep 2007
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From: Baton Rouge Louisiana
Flush?
At what frequency is flushing recommended? I have a 2002 w/ 76k, and I doubt that the coolant has ever been changed. I know I haven't anyway. Lately I have noticed a water temperature increase when running the heater (235-245 degrees), but it levels out to about 200-212 when driving normally. Advice?