Dex-cool newbie can't decide

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3,392
Location
Raleigh ,NC
My mother in law just bought a 2005 Buick. On the coolant bottle it says Dex-cool. First time for me. Inside it is red and gungy. With a red scum on the side of the bottle.I have read up on the forum on Dex-cool but I still can't decide to flush it and refill with Dex-cool or flush it and refill with Prestone all vehicle long life. i have read horror stories on Dex-cool and am leaning to ending the relationship before it starts. Plus Ace Hardware has the Prestone cheap after rebate. Thanks.
 
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19,528
Location
Lake Forest, CA
I think you should completely flush out the current Dex-cool and replace with Peak Global Lifetime that you can buy at NAPA, it is a little expensive at around $16-17 a gallon concentrate, but you don't need to change it for 5-6 years or longer.
 
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1,353
Location
michigan
Nothing wrong with dex cool. It was faulty engineering on the intake gaskets and a bad intake design. I am friends with a physicist/ chemist who was a participant in the defense of the lawsuits. She has many years in automotive engineering and we debated dex-cool for years. She said that from all the tests , that there was never a cause and effect from the coolant. With all that hogwash being said, i still would change to another brand because its easier to find and less expensive. I like Prestone long life myself.
 
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8,576
Location
Ohio
Prestone all makes is a version of Dexcool and arguably not even the best. Dexcool works great but can run into problems with cap on radiator systems especially if there are coolant leaks. Many Buicks of that age have the cap on radiator. But if it doesn't I would stick with dexcool. Otherwise you could go with Peak Global.
 
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1,392
Location
Charlotte, NC
I've never had a problem with Dex-Cool. The vehicle in my autosignature with 334K+ miles has used Dex-Cool since Day 1 and I prefer to use that over stuff that is said to work with all makes and models. I think maintenance plays a role when it comes to Dex-Cool. I think sometimes when folks have "issues" with certain things, when you question them about maintenance and you get a blank stare, that in itself could tell you everything. As far as gaskets/manufacturing flaws in gasket materials, I have no awareness about that, but to me, if it's designed from the factory to use Dex-Cool, it should work. If you feel uncomfortable with using Dex-Cool, try one of the other "all makes all models" brands of coolant after a thorough flush and report the results to us periodically. As far as brands, I use Prestone.
 
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1,392
Location
Charlotte, NC
Originally Posted By: mechanicx
Prestone all makes is a version of Dexcool and arguably not even the best. Dexcool works great but can run into problems with cap on radiator systems especially if there are coolant leaks. Many Buicks of that age have the cap on radiator. But if it doesn't I would stick with dexcool. Otherwise you could go with Peak Global.
Hey mechanicx, what's a brand that performs "better" than Prestone? I used to use Zerex back in the day and loved it, and just found a NAPA that sells it. I liked Zerex alot, but stopped using it due to lack of availability. I'm just looking for suggestions whenever I can improve my maintenance.
 
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19,528
Location
Lake Forest, CA
My LS400 had been using Preston and Peak All-Makes with tap water for many years without problems, as long as I flush the system every 3-4 years with Preston T-Flush. But Peak Global Lifetime is a better antifreeze and lasted longer, that why I recommend it.
 
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5,091
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USA
I have heard that if air gets in the system,Dexcool turns to an acid that eats gaskets,and heater cores.....???? Also,if the GM intake gasket design is so good,why was it redesigned....after everybody has an intake failure? Never used to hear of intake leaks before the late 90s (when DC came along).
 
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14,671
Location
The Old North State
What mechanicx said above. Choices listed between DexCool and Prestone AM/M LL, a Dexclone, might as well use the spec'd real deal DexCool. Hopefully your intake manifold gaskets are resistant to Dex/2eha. Peak Global Lifetime, good (no 2eha) alternative.
 
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8,576
Location
Ohio
Originally Posted By: qdeezie
Originally Posted By: mechanicx
Prestone all makes is a version of Dexcool and arguably not even the best. Dexcool works great but can run into problems with cap on radiator systems especially if there are coolant leaks. Many Buicks of that age have the cap on radiator. But if it doesn't I would stick with dexcool. Otherwise you could go with Peak Global.
Hey mechanicx, what's a brand that performs "better" than Prestone? I used to use Zerex back in the day and loved it, and just found a NAPA that sells it. I liked Zerex alot, but stopped using it due to lack of availability. I'm just looking for suggestions whenever I can improve my maintenance.
I prefer Havoline and Zerex's version of Dexcool. However Prestone works pretty especially in pressurized reservoirs like on the cavalier. I jsut believe the other two brands formula is slightly easier on plastic gasket material and more resistant to guming.
 
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8,576
Location
Ohio
Originally Posted By: NHGUY
I have heard that if air gets in the system,Dexcool turns to an acid that eats gaskets,and heater cores.....???? Also,if the GM intake gasket design is so good,why was it redesigned....after everybody has an intake failure? Never used to hear of intake leaks before the late 90s (when DC came along).
Dexcool doesn't really turn acidic and disolve gaskets or metal parts when air gets into the system. It just doesn't provide corrosion protection and gums up if air is in the system. GM changed the intake gasket design around the same time as they adopted dexcool. But the gasket was not a durable design and would eventually deteriotate and leak even if the old green coolant was used.
 

rshaw125

Thread starter
Messages
3,392
Location
Raleigh ,NC
Thanks for the replies. It seems to be a lot of negative thoughts on Dex-cool. The internet is loaded with it. I bought two gallons of Peak long life all makes and that's whats going in after a complete flush. I have it in two other vehicles. No problems.
 
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25,985
Location
Upstate NY
Originally Posted By: rshaw125
Thanks for the replies. It seems to be a lot of negative thoughts on Dex-cool. The internet is loaded with it. I bought two gallons of Peak long life all makes and that's whats going in after a complete flush. I have it in two other vehicles. No problems.
Flush with distilled water and then refill with 50/50 John Deere Cool Guard II and you will have the best and longest lasting coolant available.
 

rshaw125

Thread starter
Messages
3,392
Location
Raleigh ,NC
So Peak Long Life is a Dex-Cool clone. Is the Peak Global G-05? Maybe I should return my Peak Long Life and get the Peak Global? Thanks.
 
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25,985
Location
Upstate NY
Peak Global is not G-05. I would use peak Global over Peak Long Life. G-05 is great coolant. I run it in Jeep and 93 Chevy. It does have a very low level of silicates. So for engines that specify no silicates, I would use Peak Global or if an Asian vehicle then Zerex Asian.
 
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19,686
Location
Sunny Florida
Dexcool does not magically become acid and eat the gaskets. That's internet nonsense. There are revised gaskets that solve these issues well, not revised coolants. And the air thing is a bit in dispute here as well. Our fleet trucks have an elaborate water/water heat exchanger in the cooling system and thus have more than 2.5 times the volume of a regular truck. This also means there is virtually ALWAYS air present somewhere in the miles of hoses used. Never had a single problem. Of course these are just V-8 trucks, different platforms may have different issues.
 

rshaw125

Thread starter
Messages
3,392
Location
Raleigh ,NC
Originally Posted By: SteveSRT8
Dexcool does not magically become acid and eat the gaskets. That's internet nonsense. There are revised gaskets that solve these issues well, not revised coolants. And the air thing is a bit in dispute here as well. Our fleet trucks have an elaborate water/water heat exchanger in the cooling system and thus have more than 2.5 times the volume of a regular truck. This also means there is virtually ALWAYS air present somewhere in the miles of hoses used. Never had a single problem. Of course these are just V-8 trucks, different platforms may have different issues.
The radiator cap on the vehicle I am working on had more crude on it than any I have ever seen. There are pictures on the internet where the gasket material has been visibly eaten away.Kind of reminds me of people defending the Chrysler 2.7 against the sludge problem. I owned one and it was junk.
 
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Messages
8,576
Location
Ohio
Originally Posted By: rshaw125
So Peak Long Life is a Dex-Cool clone. Is the Peak Global G-05? Maybe I should return my Peak Long Life and get the Peak Global? Thanks.
Yes, no, yes lol. Air can be a problem with dexcool causing sludge but it doesn't make it eat gaskets. The coolant level has to be full. If the reservoir is a high mounted pressurized type and doesn't run empty (therefore the rest of the cooling system doesnt run low or have air) then no problems ensue. Go with Peak Global, G-05 or Green. Sounds like this car needs a serious flush job maybe with a T-flush with some radiator flush cleaner and probably a new radiator cap if you want to make it right. What model and engine is this car? I don't want to sound too alarming. On the W-bodies the caps can get gummed up but usually the rest of the system doesn't get too bad.
 
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