Has the DexCool "problem" been resolved?

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Dec 1, 2014
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I've been reading about the DexCool "problems", the lawsuit, etc. I see even some folks here at BITOG refer to it as "DeathCool". If I understand the true problem correctly, "...GM also started using plastic intake manifold gaskets with a silicone bead around the ports. For some reason (and NO ONE agrees on why this happens) the gasket material and Dex-Cool interact with one another, causing leaks.." and "...So it's true that DexCool caused gasket leaks, but the real problem was incompatibility between the plastic and the coolant. Everyone assumes the problem was Dex-Cool, when in fact, the problem was the type of gasket material combined with the use of Dex-Cool. GM has redesigned the gaskets that the problem has now been fixed. GM still uses Dex-Cool coolant and there is no longer a problem with gasket coolant interaction..." (Source: https://bit.ly/2FJtUTW) Has this interactive problem between the gasket material and the DexCool been resolved? Have any of you experienced recent problems? Does the use of DexCool make you worry about GM vehicles since it's the current recommended coolant? Thank you, Ed
 
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If the intake gasket was replaced with an upgrade one then the problems are resolved. DexCool is a great coolant. There have been a few other issue involving air getting into the system. I would only use DexCool in a system that came from the factory with DexCool..
 
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I used Peak and Prestone (dexcool clone variety) in a 97 Accord. I had leaks and even a blown hose, but can't say for sure it was the coolant since the car had some mileage (260k).
 
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Back in Arizona. Finally
In a vehicle designed for it Dexcool is an excellent coolant. I flushed the coolant in my FX4 at 6 years and 100k and the stuff was clean as could be. There's been pics here of cooling systems being serviced and the Dexcool kept everything pristine.
 
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I have had great results with Havoline Dexcool, even when I had my 95 K1500 "first year for Dexcool on GM trucks" with a vented coolant overflow tank! It also carries the spec for my 2011 F150 Orange Coolant WSS-M97B44-D.
 
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Wasn't the biggest issue air in the system coupled with iron blocks? I thought traditional silicate/phosphate anticorrosion additives were pretty good in those cases.
 
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These are the redesigned GM intake gaskets: https://www.google.com/search?q=GM+...399j0j8&sourceid=chrome&ie=UTF-8 No, there is no longer an issue. I speak as a current owner of 3 engines (GM 3.8L V6) and 2 in past years with a combined mileage of over 600K; and updated gaskets on all of them; along with replacing the (likewise notorious) plastic coolant elbows. Replace those elbows with the aluminum Dormans and use OE AC/Delco Orings on the elbows; then the engines are bulletproof. Don't take my word for it; take Trav's: https://www.bobistheoilguy.com/foru...es-camaro-firebird-3-8-have-#Post5047854
 
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Here is a pic of Dexcool that was in a Chev LS iron block engine for 5 years. No problems.

8C031F81-3D7E-4BFC-8E0D-A48228A8A125.jpeg
 
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Joined
Jan 7, 2008
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TX
I had a '96 Buick with the Dexcool in it, and found the Dexcool to be fine. Like you said, it was the lower intake manifold gaskets and upper manifold plenum material around the EGR stovepipe that were the issues. I replaced those with upgraded aluminum gaskets/upgraded plenum as a preventive measure. The LIM gaskets were degrading. Easy job, just time consuming with a lot of disassembly and cleaning. Fortunately, the GM 3.8L was easy to work on. Had Dexcool in a late model Malibu, no issues. Like it says though, replace Dexcool within 5 years, not necessarily because it'll fail in boil over or freezing, but because corrosion inhibitors get depleted.
 
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Have a good bit of experience with Dexcool because I experienced it first hand on a brand new 98 Malibu. Round about 27,000 miles the lower intake gasket went bad, and coolant system was a mess. My Malibu did have a pressurized coolant tank no radiator cap. Local GM dealership fixed it under warranty. Another 9,000 miles and it would have been on my dime. No idea what gaskets they used for warranty work in 2001. Car was totaled at 98,000 miles. The coolant system stayed clean after the lower intake repair.
 
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Running Dexcool in the 06 Escalade and the 05 Malibu Classic. Both have sealed systems at the reservoir. No buildup of anything inside the radiators. No crud in the tanks. It does stain the plastic reservoirs. The plastic heater core quick connects on the Escalade failed at 150k. That was bad. But I can't say the dexcool made them brittle. The hoses are are ok. If I had a choice I would run Toyota coolant. But nothings broke in the cooling systems and Dexcool is cheap. So I may start dropping the lower radiator hose every other year.
 
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Originally Posted by Snagglefoot
Here is a pic of Dexcool that was in a Chev LS iron block engine for 5 years. No problems.
What was the coolant water ratio?
 
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Keep your overflow tank filled to the "Hot" line, when the engine is COLD... Air is the enemy... No problems with Dexcool, but when I flush/fill, I am using Xerox G-05. No plasticizers in that brew...
 
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Originally Posted by Snagglefoot
Here is a pic of Dexcool that was in a Chev LS iron block engine for 5 years. [Linked Image] No problems.
Is that some antique coolant tester?
 
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Even today, you will find people who are quick to say "but 2eha is a plasticizer!" any time dexcool is brought up, shunning its use even though it's very likely that gasket materials nowadays do account for its effects. Prestone all makes or supertech premix antifreeze are probably the top selling coolants by volume and we aren't hearing about an epidemic of failed engines due to coolant leaks. I think, as long as the car being discussed was manufactured after 2005, then we can put the dexcool fear to rest. I'm tired of the fear mongering.
 
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Oct 9, 2004
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Originally Posted by edwardh1
the real question is: whatever they changed gaskets or the coolant- why did they let the customers do the testing? and not test it themselves FIRST???????
There have been theories that Dexcool Deathcool was a direct factor in the GM bankruptcy of '07, too many PO'ed customers & warranty claims.
 
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I have a '97 C2500 HD with the 5.7. At about the 6 or 7 year point and around 65k miles the LIM started leaking (coolant had been serviced at the 5 year point). Bought new gaskets from the dealer and installed them (no clue if they were improved or not). Read about the gasket/Dexcool problem a year later and drained the Dex to use G-05 because 1) I wasn't sure if I had upgraded gaskets, and 2) I suspected if the LIM was incompatible, other gaskets might be also. No problems in the last 15 years or so with G-05 the truck. No problems at all with the multiple LS engines I have had since 2001 (dry intake manifold) in other vehicles . I suspect any Dex/gasket problem would have surfaced by now if it ever will. Unless it's someone who switched from Dex in a vehicle with incompatible gaskets a long time ago, then the vehicle was switched back.
 
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That whole thing is a wives tale. The Dexcool never ate the gaskets. The gaskets failed because they did not have the necessary steel reinforcement.
 
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