Dex-Cool?

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Dex-Cool ate the intake manifold gasket on my 1997 C2500 Chevy truck. The anti-freeze and stock gasket material were incompatible. I believe GM has fixed that problem. Not sure what year, but I wouldn't use it on a pre-1999 GM vehicle.

Other than that, I've been happy with the stuff. At 12 years old, the radiator is clean as a whistle. I flush and fill at the 5 year points, and don't let air into the system.
 
The Toyota sludge problem is caused by neglecting to change the oil, not by coolant sludging up.
 
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Originally Posted By: Donald
Originally Posted By: harley145000
tdi-rick,it was never flushed,my point was g.m. says it will last 100,000 miles.But after 22,000 miles on the dex cool was turning the cooling system into sludge.That why I flushed it out and put prestone in that is for all makes and models.


One might guess you put back in a Dex-Clone, which is almost as bad as DexCool. Check if what you put in contains 2-EH, if it does, then its a Dex-Clone.

You want a Zerex G-05 or Peak Global, neither of which has 2-EH. Peak Global even boasts about being non 2-EH.


Yellow Prestone IS Dex-Cool. All makes, all models IS DexCool. Unlicensed, they don't call it that, but that's what it is. Meanwhile, I ran the Prestone orange licensed DexCool for 9 years, three flushes on up to 288,000 miles in my 92 Elantra. Never a bad water pump, leak, deterioration in the thermostat or even a trace of sludge. Had the foreign manufacturers been the ones to develop or use DexCool, it would never have had a bad rep.

Only with GM do we hear of sludge, deteriorated seals, and bad components, in keeping with overall crummy quality standards and engineering detail. The ill-advised use of plastic in critical applications is yet another example of why GM is on the ropes, and because they're an American brand, the stink spreads to all other American brands, deservedly or not, to the benefit of the foreign manufacturer. It's not the Dexcool, its the GM.
 
Originally Posted By: toocrazy2yoo
Originally Posted By: Donald
Originally Posted By: harley145000
tdi-rick,it was never flushed,my point was g.m. says it will last 100,000 miles.But after 22,000 miles on the dex cool was turning the cooling system into sludge.That why I flushed it out and put prestone in that is for all makes and models.


One might guess you put back in a Dex-Clone, which is almost as bad as DexCool. Check if what you put in contains 2-EH, if it does, then its a Dex-Clone.

You want a Zerex G-05 or Peak Global, neither of which has 2-EH. Peak Global even boasts about being non 2-EH.


Yellow Prestone IS Dex-Cool. All makes, all models IS DexCool. Unlicensed, they don't call it that, but that's what it is. Meanwhile, I ran the Prestone orange licensed DexCool for 9 years, three flushes on up to 288,000 miles in my 92 Elantra. Never a bad water pump, leak, deterioration in the thermostat or even a trace of sludge. Had the foreign manufacturers been the ones to develop or use DexCool, it would never have had a bad rep.

Only with GM do we hear of sludge, deteriorated seals, and bad components, in keeping with overall crummy quality standards and engineering detail. The ill-advised use of plastic in critical applications is yet another example of why GM is on the ropes, and because they're an American brand, the stink spreads to all other American brands, deservedly or not, to the benefit of the foreign manufacturer. It's not the Dexcool, its the GM.


OK, so maybe GM did a lot of other crummy quality standards things and that caused the DexCool to turn to sludge. Had GM used G-05 they might have still had the various leaks and gaskets would need to be replaced, but there would not be any sludge.

No one is saying every car using DexCool will have sludge, but has anyone said a car using G-05 has had sludge for any reason?
 
So, to sum things up, there appears to be multiple problems and interactions that have resulted in the GM/Dexcool fiasco. Dexcool can not be blamed alone because it does work in certain applications in spite of the 2EHA.

Correct me if wrong, but GM has changed its gaskets over the years, indicating problems that may have occurred regardless of coolant type. Has anyone used a different coolant during the peak problem years and avoided the gasket malfunction?

Sludge and/or gasket degradation seem to be the potential results of one or more these various interactions occurring when the stars are in proper alignment.

Did anyone here at BITOG take advantage of the warranty extension GM offered (now over, I believe)to cover repair costs?
 
Originally Posted By: doitmyself
So, to sum things up, there appears to be multiple problems and interactions that have resulted in the GM/Dexcool fiasco. Dexcool can not be blamed alone because it does work in certain applications in spite of the 2EHA.


It likely is several factors. I'm beginning to think part of the problem was that 2EHA by itself didn't prove to be very effective in protecting iron, so the block and the heads if made of iron would rust if air got in the system. This may be why 2EHA began to be used along with protectors, as in Prestone
 
Prestone Dexcool in my 93 MB 190e 2.3 since I replaced the water pump at 91,000 miles. Just turned 197,000 and everythings fine. When I drain it every 2 years or so it comes out looking like new. Of course my head gasket will probably go tomorrow!
 
Any coolant that would turn to sludge because of air pockets has to be considered detremental to a cooling system. Just because some vehicles haven't had a problem doesn't mean that Dexcool is off the hook. Do some of you people really want to trust your $25,000 vehicle to an inferior product with so many alternatives? That doesn't make any sense at all. We debate oil ad nauseum on this forum, when pretty much any brand of oil will provide adequate lubrication for all engines but excuse away an obvious defect in one particular coolant? Can you imagine if Mobil 1 caused Corvettes to sludge up only under certain circumstances? Nobody would want to use it. Come on wake up and smell the Dexcool sludge. BTW, if Dexcool is so good, why don't any other manufacturers use it? 'Cause they tested it better than GM and rejected (Ford, Chrysler, VW, and MB all tested and rejected it.) I refuse to try to reason with any more of you Dexcool lovers. Use it and play Russian roulette except half the chambers are loaded. I learned my lesson the hard way, you re-invent the wheel yourself.
 
Originally Posted By: toocrazy2yoo


Only with GM do we hear of sludge, deteriorated seals, and bad components, in keeping with overall crummy quality standards and engineering detail. The ill-advised use of plastic in critical applications is yet another example of why GM is on the ropes, and because they're an American brand, the stink spreads to all other American brands, deservedly or not, to the benefit of the foreign manufacturer. It's not the Dexcool, its the GM.



What???

GM is giving Ford and Chrysler a bad name???
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Originally Posted By: toocrazy2yoo
Had the foreign manufacturers been the ones to develop or use DexCool, it would never have had a bad rep.


Some foreign manufacturers do use something close to DexCool, all in Europe.

The Japanese have turned two thumbs down on it universally.

Ford ran it in the Cougar one year for a full evaluation and then dropped it.

When DexCool works, it's fine.

However, it's intolerant of some very common maladies - low coolant, cavitation, air bubbles.

Both the Japanese coolants and G-05/G-48 take the basic OAT concept, delete the 2EHA, and add a bit of something to take care of the problems that DexCool can't handle. In G-05/G-48 it's silicate, in the Japanese coolants it's phosphate.

Basically they do what DexCool does, but handle what DexCool can't.


.
 
Originally Posted By: ZGRider
Any coolant that would turn to sludge because of air pockets has to be considered detremental to a cooling system. Just because some vehicles haven't had a problem doesn't mean that Dexcool is off the hook. Do some of you people really want to trust your $25,000 vehicle to an inferior product with so many alternatives? That doesn't make any sense at all. We debate oil ad nauseum on this forum, when pretty much any brand of oil will provide adequate lubrication for all engines but excuse away an obvious defect in one particular coolant? Can you imagine if Mobil 1 caused Corvettes to sludge up only under certain circumstances? Nobody would want to use it. Come on wake up and smell the Dexcool sludge. BTW, if Dexcool is so good, why don't any other manufacturers use it? 'Cause they tested it better than GM and rejected (Ford, Chrysler, VW, and MB all tested and rejected it.) I refuse to try to reason with any more of you Dexcool lovers. Use it and play Russian roulette except half the chambers are loaded. I learned my lesson the hard way, you re-invent the wheel yourself.


How soon we forget. I started using Dexcool shortly after it was introduced so that I could get away from the horrors of the old conventional green sludge. Dexcool worked well in the cars I used it in and stayed clean.

Today, every common coolant is a Dexcool derivative. There must have been something they were doing right.
 
Originally Posted By: ZGRider
Any coolant that would turn to sludge because of air pockets has to be considered detremental to a cooling system. Just because some vehicles haven't had a problem doesn't mean that Dexcool is off the hook. Do some of you people really want to trust your $25,000 vehicle to an inferior product with so many alternatives? That doesn't make any sense at all. We debate oil ad nauseum on this forum, when pretty much any brand of oil will provide adequate lubrication for all engines but excuse away an obvious defect in one particular coolant? Can you imagine if Mobil 1 caused Corvettes to sludge up only under certain circumstances? Nobody would want to use it. Come on wake up and smell the Dexcool sludge. BTW, if Dexcool is so good, why don't any other manufacturers use it? 'Cause they tested it better than GM and rejected (Ford, Chrysler, VW, and MB all tested and rejected it.) I refuse to try to reason with any more of you Dexcool lovers. Use it and play Russian roulette except half the chambers are loaded. I learned my lesson the hard way, you re-invent the wheel yourself.


How soon we forget. I started using Dexcool shortly after it was introduced so that I could get away from the horrors of the old conventional green sludge. Dexcool worked well in the cars I used it in and stayed clean.

Today, every common coolant is a Dexcool derivative. There must have been something they were doing right.
Originally Posted By: Rolf
Originally Posted By: toocrazy2yoo
Had the foreign manufacturers been the ones to develop or use DexCool, it would never have had a bad rep.


Some foreign manufacturers do use something close to DexCool, all in Europe.

The Japanese have turned two thumbs down on it universally.

Ford ran it in the Cougar one year for a full evaluation and then dropped it.

When DexCool works, it's fine.

However, it's intolerant of some very common maladies - low coolant, cavitation, air bubbles.

Both the Japanese coolants and G-05/G-48 take the basic OAT concept, delete the 2EHA, and add a bit of something to take care of the problems that DexCool can't handle. In G-05/G-48 it's silicate, in the Japanese coolants it's phosphate.

Basically they do what DexCool does, but handle what DexCool can't.


.


For the record, Ford introduced Dexcool on the 99 Cougar and retained its use in the Cougar until the Cougar was dropped from production at the end of the 2002 model year. The engines and cooling systems were identical to Contours and Mystiques for 99 and 2000 until Contours and Mystiques were dropped from production.

Pre-production literature for the 2000 Continental showed that Dexcool would be used on it too, but it never happened.
 
Originally Posted By: Big Jim

Pre-production literature for the 2000 Continental showed that Dexcool would be used on it too, but it never happened.


Gotta ask yourself 'why'.....
 
Originally Posted By: Big Jim
Today, every common coolant is a Dexcool derivative.


That's not quite accurate.

OATs in general preceded DexCool.

HOATs, for example, are an OAT plus an inorganic inhibitor of some sort.

Mercedes went to G-05 in the 80s.

I have used DexCool in some personal vehicles with no problem.

In a fleet, though, you start seeing its Achilles heel.

When it works, it works great.

When it fails, it fails catastrophically.



.
 
Originally Posted By: Rolf

When it works, it works great.

When it fails, it fails catastrophically.


That has been my experience, too.

I've seen automotive systems filled with Dexcool pushing 200k miles that were squeaky clean... and long-haul trucks approaching 800k with new-looking cooling systems filled with Dexcool.

I've also seen LOTS of GM autos/light trucks with thoroughly sludged cooling systems at well under 100k miles. I've seen Dexcool cause DOZENS of perfectly good Cummins N14 head gaskets to leak before 200k (barely broken-in for a long-haul truck). These were paid for under Texaco warranty.
 
None that I'm aware of except possibly resale value- some buyers might be worried if they see that you've put in the 'wrong' antifreeze.

Of course, you could fill with Mopar G05 if that was a concern- it's red/orange just like dexcool.
 
Who knows what the "wrong" antifreeze is, anyway? It isn't like we get to talk to the folks that built the cars. This new 2008 Hyundai I have specs a coolant change at 60K, 30K thereafter. Does that mean the syrup at the factory is "better"? My 2005 Accent had snotty, settled out of solution silicate swimming around in there the day they delivered it (it was built in Nov. 2004, I took delivery Feb. 2006), so I changed it out to G-05 at around 1000 miles when the dealer wouldn't replace the coolant. They didn't care if I changed it, but THEY weren't going to. G-05 should be good, right? G-05 is a nice clear Hybrid OAT, with a dash of silicate, it was spoken of highly here, so I flushed it but good with distilled water and went 50/50 G-05. What happens? New waterpump at 44,000. Do I blame the coolant? Not necessarily. Maybe the car sat on the lot too many months, who knows, but it DID fail with G-05. On my 1992 Elantra, the water pump only got changed every second timing belt, never for failure. The 92 Elantra? Orange DexCool licensed clone from Prestone. But I changed it every 30K.

I called the dealer to ask what to use on the 2005, they told me not to use DexCool, use yellow Prestone, which IS Oat, no silicate, an unlicensed DexCool clone, just like their orange Dexcool, without the orange, of course. So even the dealer doesn't know. Hyundai America doesn't know. The dealer doesn't know what Hyundai put in at the factory in Korea, nor does Hyundai America. The owner's manual says to use a good-quality ethylene-glycol coolant. Period. You're on your own.

So we're at the crux of the matter. And I doubt Hyundai is unique in this, at least amongst the foreign manufacturers. Go on, try to find out precisely what coolant they put in at the factory, in a foreign-built Toyota, Honda or Nissan. I defy you to get the same answer twice. Where does that leave us? Right back at the door of sound maintenance practice. Change the stuff once a year, pick one coolant and stick with it. If your car goes two years and you're comfy with that, the same coolant for all that time, go with it.

But seriously you guys, show of hands here, WHO REALLY thought 10 years ago that going 5 years and 100,000 or 150,000 miles on the original coolant was a good idea? Anyone think 100,000 miles on a set of plugs is a good idea? Those intervals invite negligence. Furthermore, far better than 99.999% of the motoring public, the folks right here on these pages know dammed good and well there was no car that was going to survive the maintenance practices GM specified for those V-6s back then. That's no matter the plastic manifolds, the DexCool or the bad gaskets. Those specs weren't prudent, they didn't make sense, and the predictable results slathered on more bad rep to the GM lineup.

So stop with the Dex-hate. It's nonsensical. Look at it this way if you will: In the lubrication realm, much has changed, better fuel control,alloys, base oils, additives, all pointing toward longer drains. But other than silicate reduction, and OAT, not much has changed in ethylene-glycol coolant since the old shade-tree days and nothing in cooling system design and construction has changed for the better. In modern cooling system construction, we have aluminum blocks, not iron, we have thin, crummy, plastic-tanked radiators with thin-walled aluminum tubes, not radiators with beefy, soldered brass and copper side-tanks with thick-walled tubing. Heater cores are crummy now, too. Everything is considerably different, but we're to believe that we can go 100,000 or 150,000 miles on these cooling systems as delivered today? Sorry. I don't buy it. And to blame it on the COOLANT is preposterous. To me, that is as nonsensical as blaming Pennzoil for the sludge in the engine that didn't get the oil changed for 15,000 miles.

My humble opinion, your mileage may vary.
 
I have never trusted whats printed in my owners manual. IMO all that stuff is the companies Marketing Department trying to make us feel better. "Look you can go 100,000 KM before your first service" etc.

I always have done testing of the various fluids: UOA's with TBN on Oils, Coolant test strips for strength and acidity, taking the plugs out before 100K and looking at them. Changing the PS fluid every 100K and flushing the brake fluid every 2 years when I change my brakes (do a lot of driving).

This system has never failed me!
 
Point taken and made, there, Stevie-boy!
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It's all elementary to me too. One thing the Hate-Dex folks never argue: had they changed the coolant every year, been observant, taken a little care, the disaster wouldn't have happened. But no, they want to think nothing of it for five years. Reap what ya sow when it comes to maintenance, baby!
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