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DEXCool Coolant.  Is Anybody Switching It Out?

jdw174

Full Member
Joined
Jan 5, 2003
Messages
128
Location
Paris, TN
From another website's towing/trailering forum I read that GM's DEXCool (called "DEATHCool" on the other forum) will actually turn to mush in your cooling system if the system develops a leak anywhere allowing air into the system. :eek: Several advocated completely draining the system and replacing it with "green" coolant.

Anybody here ever heard of such a thing? Hardly seems like they would use coolant like that, but I suppose stranger things have happened.
 
I have heard thea when air is introduced into the cooling system dexcool turns corosive. I would not worry until something happens ie. hose replacement, water pump, thermostat, etc., then I would go back with green stuff.
 
I have one question! Why doesn't our DEX Cool instantly turn corrosive then? The overflow is exposed to air. Then some of this gets mixed with the rest in the radiator. What about that? They say that if the overflow gets low you fill that up. I don't have any way of putting fluid in with out air getting into it. Also how did they get the DEXcool in in the first place it had to be exposed to air somewhere. Sounds like FORD trying to get a bad rumor started. GM also states that with DEXCool you only need to replace it every 100K, while the green stuff says every 50K. Just my $.02.
 
Here is the thread I got this question from:

I have heard to "Get it out and put in green" and Ive heard "leave it alone" Does anyone really know ?



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3/11/03 3:20:00 PM Submitted by Foy (24.199.149.133) from NORTH CAROLINA says DeathCool
I certainly don't "really know" but I've read enough negative comments about it to cause me to get rid of it, anyway. Plus, GM steadfastly says "no problem" with DeathCool, and any time GM says that, I duck for cover.
For lots of print, including links to Texaco's own release, find the VMag board on Suburbans and Tahoes and do a search. You can also link to #1 Son's Suburban site, where there's a whole section on cooling system woes.

My $00.02



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3/11/03 8:35:00 PM Submitted by Lee (67.29.255.93) from TEXAS says Was going to replace with green, but was talked out of it
by my favorite mechanic. According to him, the problems develop when air gets introduced into the system. As long as the system doesn't start to leak there is usually no problem. When DexCool mixes with air it turns a mud brown color and the consistency gets like sludge, which plugs up cooling passages causing overheating. A descent way to check is simply to look inside the radiator cap. If it's "muddy", problems are rapidly developing. You can also pull a little fluid into a syringe and make sure it's still orange and clear, not brown/cloudy or with particles floating in it. (A good thing about the green coolant is that it doesn't react negatively to air in the system.) I just check mine regularly and keep it filled full of DexCool. At 58K, so far no leaks. By the way, if you do swap coolants make sure you have ALL the DexCool out and the system is thoroughly flushed first.


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3/11/03 10:20:00 PM Submitted by Beartrap from GEORGIA says it don't last 100,000 miles either
at about 70,000 miles,it turned to sludge in 97 Jimmy,dealer said they guarranteed that it would "protect against freezing" for 100,000 miles which is really false and misleading since their advertising lead you to believe that you didn't need to touch it for that many miles....ended up taking to radiator shop and getting system cleaned out and heater coil replaced.....radiator shop said this was commonplace with dexcool and recommended changing it every two years...


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3/11/03 10:51:00 PM Submitted by McCoy from TENNESSEE says Dexcool
I've got about 110,000 miles on my van with dexcool in it. From what I've read, you need to make sure the coolant stays up to the full mark on the reservoir and don't be taking the radiator cap off. When you get about 150,000 miles on the vehicle, trade it off and let someone else worry about it.


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3/12/03 9:23:00 AM Submitted by Foy (165.247.156.164) from NORTH CAROLINA says Exactly my point.........
Anybody who comes here often is likely a maintenance buff, so on the one hand, checking the failure potential of DeathCool regularly can ward off the problems that arise when air gets into the cooling system, or when you try to keep the stuff in the engine for the entire recommended service life, etc. On the other hand, and IMHO, why would you want to keep a product in the cooling system that is known to deteriorate rapidly under certain identified conditions, and can ruin your engine if you inadvertently skip a "check date" and fall victim to sludge formation and cook the engine? I just wonder where the upside is if you've got to check it regularly and it needs changing regularly. Me, I choose to go with something I know--the green stuff.


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3/12/03 12:30:00 PM Submitted by Glennn AbuElHaj (64.175.80.17:cool: from CALIFORNIA says Exactly Foy....
Get rid of that crap and switch to green. Heck, I'd rather run straight water than the deathcool schitt!!
Good luck!



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3/12/03 12:34:00 PM Submitted by Jeff_S (162.89.0.62) from TEXAS says Change It!!
My cousin has been a mechanic for a long time at a local dealership which is very successful. He said he isn't gonna try to persuade anyone to change it due to liability reasons, but he changes it on his own vehicles. He said he has seen enough to persuade him. The intake manifolds leaking on Chevy 5.7 litres is being blamed on this DeathCool. Also, the corrosion on many of the metal plumbing pieces on the cooling system is blamed on DeathCool. I changed mine out years ago and haven't had a single problem. I changed it after removing the corroded metal piece that comes out of the intake manifold that was having holes eaten into it from the inside out. The green stuff is proven, just don't pour it into the creek or feed it to the kids.


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3/12/03 3:54:00 PM Submitted by Phill (136.200.212.33) from CALIFORNIA says Agree with the majority here
I experienced it. My '99 suburban developed a leak at the heater core nipple going into the intake manifold at around 25k miles. They replaced it under warranty. Then, at around 36k miles, the intake manifold gasket deteriorated causing leakage. They repaired that under warranty, reluctantly. Then, at 45k miles, the d@mn heater core nipple corroded and leaked again. During that time, a mechanic friend told me to switch to the green stuff because he read in some bulletin that the "brown" dexcool was dielectrically incompatible with certain metals, causing corrosion. He doesn't work for GM, has his own shop. Apparently, dexcool accelerates electroloysis between the metals and coolant when air mixes in with it.
Well, I've always kept the overflow tank full but found that when the engine cools down, and it sucks the coolant back into the radiator, it always leaves a bubble worth of air which during intial startup before heat starts to expand it, that bubble gets circulated into the block and system.

After I changed to the green stuff, I am now at 70k miles and not a problem yet with corrosion caused leaks (knock on my wooden head....). I use distilled water, 60-40 mixture, and change every year. That's cheap, compared to the fixes.



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3/13/03 12:58:00 PM Submitted by Troy (208.163.187.124) from MICHIGAN says Always the same thing
If it isnt breaking, the manufacturer isnt making money off spare parts and dealer service. So make it so it eventually breaks. The green stuff was making parts last too long, so to help fill their deep pockets they had to switch to something that would destroy the cooling system, hopefully just after the warranty expires.
Everywhere Ive read a discussion about coolant, it seems DeathCool causes problems that rarely or never existed with the green stuff. I read once that it was supposed to provide better compatibility with the modern engines that use aluminum components.

Well my 1990 Chevy 3.1 engine has a lot of aluminum components, including cooling system components. I just rolled 221,000 yesterday and never have I had a cooling system problem. All the components are still original and working fine. I use the green stuff and backflush it every couple years.


 
The dexcool system is sealed. If air is allowed in the system due to a leak of a constant nature the dexcool will possibily gel up... however it's rare. I've only seen it once, on a olds van, with a cracked block. I would not recommend changing the dexcool out for all the important reasons such as warranty, better protection of engine due to better heat transfer properties, water pump lubrication, entire system designed around dexcool, did I mention warranty ? ;)
 
The stuff cost me $300 in repairs on my Bravada. I never saw anything like it. I walked into the repair shop and said " I split the radiator on my Bravada where do you want me to park?" he said "it's split at the left top about one inch down, they all do, and you'll need the whole system power flushed to get the gunk out.' This was before I even opened the hood. I didn't know it was bad antifreeze until this thread. I just thought the system went to hell....
 
Michiana Bubba said:
I have one question! Why doesn't our DEX Cool instantly turn corrosive then? The overflow is exposed to air. Then some of this gets mixed with the rest in the radiator. What about that? They say that if the overflow gets low you fill that up. I don't have any way of putting fluid in with out air getting into it. ?Also how did they get the DEXcool in in the first place it had to be exposed to air somewhere. Sounds like FORD trying to get a bad rumor started. GM also states that with DEXCool you only need to replace it every 100K, while the green stuff says every 50K. Just my $.02.


i think i will have to agree with you on this one. what about the air in the container Dex-Cool is in when you buy it? i changed out a thermostat and water pump on a Jeep cherokee yesterday. the green anti-freeze in it was foamed over from getting too much air/heat in it. so i do not see the point. ???
 
I've had DEXCool in my cavalier for 5 years and 95k miles with the only maintenance being topping it off. It's still clear and orange. The only cooling system problem I've ever had was a water pump leak that only happened 5k miles ago. I don't think 95k miles on 1 water pump is something to be blamed on corrosive "Death" coolant.

BTW, I've never heard of problems with air mixing with it, but I have been told by a good mechanic that what usually causes the brown "sludge" problem is people who mix in a small amount of the Green stuff into their DEXCool by accident. They absolutely do NOT mix and turn into a gummy mess if you do.

I'd be willing to bet that a lot of the people who've had these problems either did that themselves and are covering for their own mistake, or some quickie-oil-change schlepp dumped it in there without the owner's knowledge.

 
TXAVy said:
I've had DEXCool in my cavalier for 5 years and 95k miles with the only maintenance being topping it off. It's still clear and orange. The only cooling system problem I've ever had was a water pump leak that only happened 5k miles ago. I don't think 95k miles on 1 water pump is something to be blamed on corrosive "Death" coolant.

BTW, I've never heard of problems with air mixing with it, but I have been told by a good mechanic that what usually causes the brown "sludge" problem is people who mix in a small amount of the Green stuff into their DEXCool by accident. They absolutely do NOT mix and turn into a gummy mess if you do.

I'd be willing to bet that a lot of the people who've had these problems either did that themselves and are covering for their own mistake, or some quickie-oil-change schlepp dumped it in there without the owner's knowledge.

i agree with you. i would suspect you had air enter your system when you had the water pump changed. no negative results, right?
 
No, no negative results in the last 5k miles since the water pump was changed which required a full coolant replace.

I expect that the people who are commenting about the air problem are not saying clearly what they mean. I would imagine that if air bubbles were to circulate through the system (instead of just "touch" the fluid) then it could be whipped into a kind of froth as it passes through the water pump. This is purely guesswork, though I've seen it happen on a power steering system about 10 years ago. Once the bubbles get sucked into the pump it's a HUGE pain to get it totally bled back out again without flushing/replacing the fluid. That doesn't explain the corrosive comments though for which I'm at a loss.

I still think that many of the problems are from people who got some green stuff mixed in with their DEXCool somehow, whether they knew about it or not. That DEFINATELY causes a brown, sludgy, mess that will gum up the inside of your cooling system.

 
Under the advice of my brother-in-law, a GM serivice-tech for the last 10 years, I changed my Dex-Cool out for the green stuff as soon as I bought my used AVY with 22K on it. Seems his experience is that the Dex-Cool will eat away the head gaskets over time, not too mention the slush problem.

Sure enough, two weeks later my wife is driving her 1996 Suburban and had no heat. She was just a mile from our favorite shop, so I had her take it in. Come to find out, the Burb had Dex-Cool and had eaten away the head gaskets. No coolant - no heat!

$400.00 bucks, and new green-stuff later and she was back on the road. The service guys say it happens all the time with GM vehicles equiped with Dex-Cool.
 
AIr is in the sytem....the radiator is not completely full.....refill bottle...

Etc etc......this sounds like one of them myth things.......Anyone have proof that stands up in court for this?
 
Not air in the system... the system becoming unsealed. The Dexcool system is sealed, if there is a break in that seal (read cracked block, water pump leak, cracked hose, etc) it WILL cause porblems. I know people who swear by Dexcool and people who hate it. My thought is the same as always, preventitive maintenence schedules based on time, mileage, driving conditions, etc. should be used and not just a theory of I'll do a coolant system service every 100,000 miles. Follow the recommendations of service providers that you trust and you will experience a long vehicle life.
 
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