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About "DEX-COOL 2007"

by John R. Hess with additions from Mole Snoopster
To appear in March 2007 Cool Profit$ Magazine
2007 All Rights Reserved

New! Would you like to respond or add to something mentioned in this article? You can do so now by using our new "Comment" section at the bottom. Feel free to use it, but please keep your remarks relative to the subject. (Vulgarities, spam or libelous, denigrating comments will be deleted.)

Producing this epic took hours, days, weeks and months of reading, talking to DEX and cooling system experts and users, writing, rewriting and then starting the whole procedure over again. It has consumed more than 8 months of my life. (Yes, a lot more than it should have due to health problems.) Frankly, the difficulty was finding any one person who could factually layout the "whole" picture. I've not yet spoken to any single individual who is either able or willing to share it "all." Certainly there are plenty of engineers at GM who could. But with class action lawsuits eminent, they'll not speak to Mole, me, or any other independent automotive writer. There are also independent cooling system engineers, maybe past GM employees or venders, who could put most of the pieces together. But most of them are contracted up with the attorneys for the plaintiffs; they'll not speak to me either.

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The other major problem in sizing up the whole DEX corrosion, rust, sludge, low coolant level (sometimes right from the factory), incorrect radiator cap part and location on radiator tank, undersized overflow bottle design and incorrect placement, deteriorating intake manifold gasket thing is just that: a darn story about umpteen components and systems with counteracting, interrelated events, including service shops and vehicle owners not knowing exactly what services to perform, and all this taking place at the same time together, or not!

But, after reading through the (almost) finished project, I fear the multitude of details might be covering up the more important "Big Picture." Consequently, here's a collection of bottom line facts and opinions that hopefully highlights the import of the entire topic, while somewhat summarizing the piece as well.

1. Opinion. First of all, upfront: I have no idea whether or not General Motors breached the Magnuson-Moss Warranty Act, or violated the Missouri Merchandising Practices Act, or broke any other laws through the level of support they chose to apply to the problems associated with DEX. The juries will ultimately make that decision. Frankly, I'll support it either way. 

But I do believe GM's method for handling (or lack of) the resulting vehicular problems was certainly not in the best possible customer service manner. I wouldn't doubt if it helped give rise to the enhanced sales of Toyotas as well as other "import" vehicles. In addition, there's plenty of GM vehicle owners out there right now who wouldn't put DEX back in their machines if GM delivered jugs of the stuff free of charge to their front porch. And you know those owners are "expressing their discontent" to all their friends, family and other customers sitting in the barber shop.

2. Opinion. Ignoring the paragraph above, DEX-COOL is a fine, long-life, quality, coolant. This assumes that all of the engine and cooling system components that come in contact with it are designed to withstand the plasticizing affects of the 2EH contained in its inhibitor package. For certain affected (vulnerable) vehicles, if a better designed and built IMG is installed during a changeover, there's no reason to switch to green antifreeze.

3. Intake manifold gaskets made with a Nylon 6,6 carrier that comes in contact with DEX, at least on the 3.1L and 3.4L V6s (and probably many others), will not keep up with DEX's planned 150,000 mile service life. Even GM's own internal docs say they're failing as early as 20,000 miles.

The saga ain't over. In the last two weeks I've heard of two 2003 vehicles, one a Chevy Venture van, that both needed IMG replacements at about 60,000 miles. Sounds to me like GM has a continuing design problem with that series of gasket.

4. The S/T Blazer 4.3L sludge problem is a different makeup than sludge associated with 3.1L/3.4L engines. The Blazer's radcap/overflow bottle size and location problems are not seen in the 3.1L/3.4L series. Again, even GM's internal memos admit that the composition of the sludge is not the same.

5. It's the new guy's fault. The radical coolant color changeover in 1995-96 (the very familiar green replaced so quickly by the fluorescent, bright red-orange DEX-COOL) made it easy for everyone to pounce on DEX as the culprit for all the engine overheats and cooling system sludge-fouling that started popping up across the country. (I won't bore you with the various renaming jobs that some disgruntled vehicle owners and mechanics chose to call it.) In any case, I stand by #2 above.

Now start in with Part 1, and please feel free to call or write with your comments, corrections and questions.
John and Mole.

PS Be sure to bookmark this page as I claim the right to keep this document "open." I know I'll think of more mini-summations tomorrow or the next day, etc. Feel free to stop back any time. (This is another advantage that web-based docs have over those of ink and paper.)

If you have similar stories but maybe with differing details and outcomes, and would like to share them with Cool Profit$ Magazine's readers, please call me at 800-883-8929. Click here to email your story.   $$$

Return to DEX-COOL 2007, Part 1
Return to DEX-COOL 2007, Part 2
Return to DEX-COOL 2007, Part 3
2007 All Rights Reserved

The comments system is currently being upgraded so comments are not available at the moment. I hope to have them operational soon.