Has the DexCool "problem" been resolved?

[BigD1]

Originally Posted by das_peikko

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.

Wrong! The gaskets failed because they were being softened by Dexcool. Bill at Mahle explains the real story about Dexcool.

 

[Snagglefoot]

Originally Posted by atikovi

Originally Posted by Snagglefoot

Here is a pic of Dexcool that was in a Chev LS iron block engine for 5 years. No problems.

Is that some antique coolant tester?

Haha. Would you rather have this one?

 

[Snagglefoot]

Originally Posted by LeakySeals

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?

Somewhere around 60% Dexcool.

 

[Snagglefoot]

The problems are from 20 years ago. There's no longer any reason to worry about Dexcool. It is indeed GM's recommendation in the new owners manuals.

 

[Snagglefoot]

[quote Does the use of DexCool make you worry about GM vehicles since it's the current recommended coolant? Thank you, Ed [/quote] Problems are over now. Everyone move on.

 

[Garak]

Originally Posted by Snagglefoot

Haha. Would you rather have this one?

I may have one of each in my garage, too!

 

[dogememe]

I have no trouble with Dex-Cool in my 95 Chevy K1500 Silverado with the TBI 350, though I have had several GMT400 trucks with the Vortec 350 and every single one either needed the lower intake gaskets replaced or they had already been done. I'm thinking of switching to G-05 in the Chevy just for unity with my two Fords but why fix something that isn't broken? I'll probably just leave the Dex-Cool alone and change it next time it needs any cooling system work. Dex-Cool is a good product in a properly maintained vehicle and not mixed with incompatible coolants.

 

[atikovi]

Originally Posted by Snagglefoot

Originally Posted by atikovi

Originally Posted by Snagglefoot

Here is a pic of Dexcool that was in a Chev LS iron block engine for 5 years. No problems.

Is that some antique coolant tester?

Haha. Would you rather have this one?

No, this ain't the 70's any more, I use a coolant refractometer like this:

 

[Snagglefoot]

Very cool. I want one!

 

[Sayjac]

Quote

No, this ain't the 70's any more...

Not sure what decade I'm living in then, because pic shows all I have used to check concentration. lol Used to be a ~$1 at WM, now about ~$2. Worked/works fine ime. That said, only really needed it when had to do a subsequent premix AF d&fs when wrong coolant used by dealer. Use system capacity with concentrate AF to figure 50% concentration and change on vehicle/AF recommended intervals. So hydrometer for me just an auxiliary item. As for topic, in newer vehicles designed for and specing DexCool now I'd have no issue using it. However, would not use Dex, Dexclone (including but not limited to Prestone) or any AF using 2eha as inhibitor, in vehicles not specing it in oem AF. There's now many reasonably priced same as the oem type aftermarket AFs available.

 

[StevieC]

Dexcool is fine now because the bugs have been worked out in the cooling system of GM vehicles. That said I wouldn't use Dexcool in any other system that didn't come with it originally but in the systems it's designed for it's fine. Neighbours wife had a Sunfire and now a Chevrolet Cruz both with Dexcool. No issues. I think where a lot of the problems happened with the sludging issue which lead to the "Deathcool" slogan was people mixing things into Dexcool that wasn't compatible even though it said it might have been. Eg: "Universal coolants" used as top-off or for partial drain/fill's instead of Dexcool from GM. Similar happened with Chrysler vehicles and their OAT formulations being mixed with other stuff that shouldn't have been.

 

[FCD]

There is no problem using Dexcool in any GM car that specs it ( anymore ) the problems with gaskets were solved a long time ago, they simply made the gaskets they were using resistant to the 2-Eha Dexcool uses. While most manufacturers have now switched to OAT / HOAT formulas, the formulas vary. GM and Ford use OAT coolant with 2-Eha. VW uses a Silicated "Si-OAT" with no 2-Eha Chrysler uses a OAT with no 2-Eha. And Asian manufacturers use Phosphated "P-OAT" coolant without 2-Eha. So personally i wouldn't have a problem putting Dexcool in a Ford which has Ford's current Orange OAT coolant, but i would not put it in a VW, Chrysler or any Asian car, as their factory coolant do not use 2-Eha. 2-Eha does very nasty things in cooling systems not designed for it, swell rubber seals, hoses, gaskets, eating away at soldered radiators...

 

[BigD1]

Originally Posted by StevieC

I think where a lot of the problems happened with the sludging issue which lead to the "Deathcool" slogan was people mixing things into Dexcool that wasn't compatible even though it said it might have been. Eg: "Universal coolants" used as top-off or for partial drain/fill's instead of Dexcool from GM.

On my new 98 Malibu, I only used Dexcool for top offs, and it still turned into a coolant sludge monster. I am sure there were many thousand others that did the same with the same coolant sludge results.

 

[StevieC]

Originally Posted by BigD1

Originally Posted by StevieC

I think where a lot of the problems happened with the sludging issue which lead to the "Deathcool" slogan was people mixing things into Dexcool that wasn't compatible even though it said it might have been. Eg: "Universal coolants" used as top-off or for partial drain/fill's instead of Dexcool from GM.

On my new 98 Malibu, I only used Dexcool for top offs, and it still turned into a coolant sludge monster. I am sure there were many thousand others that did the same with the same coolant sludge results.

That's why I said... "I think" because it wasn't confirmed. Maybe you had an oil leak or exhaust leak into the coolant system just minor enough that it took time to react with the dexcool and developed into sludge. Knowing that GM can't seem to keep their fluids where they should be I wouldn't be surprised if that is what happened. It wouldn't take a lot of contamination of the coolant system for the coolant to react. It's quite fussy is my experience. Heck it could have even been a defective fill of the coolant itself although I would think the batch should be tested where its made. Who knows... If it truly were the coolant they would have stopped using it all together and every vehicle would have sludged and that didn't happen.

 

[KE7JFF]

Something I remember made things worse around 2004 with Dexcool was the fact GM was mostly on closed cooling systems with no rad cap and that confused seasoned mechanics...

 

[dave1251]

Originally Posted by dogememe

I have no trouble with Dex-Cool in my 95 Chevy K1500 Silverado with the TBI 350, though I have had several GMT400 trucks with the Vortec 350 and every single one either needed the lower intake gaskets replaced or they had already been done. I'm thinking of switching to G-05 in the Chevy just for unity with my two Fords but why fix something that isn't broken? I'll probably just leave the Dex-Cool alone and change it next time it needs any cooling system work. Dex-Cool is a good product in a properly maintained vehicle and not mixed with incompatible coolants.

Or you can move your Ford's to DEXCOOL Ford did.

 

[Railrust]

Originally Posted by StevieC

Dexcool is fine now because the bugs have been worked out in the cooling system of GM vehicles. That said I wouldn't use Dexcool in any other system that didn't come with it originally but in the systems it's designed for it's fine. Neighbours wife had a Sunfire and now a Chevrolet Cruz both with Dexcool. No issues. I think where a lot of the problems happened with the sludging issue which lead to the "Deathcool" slogan was people mixing things into Dexcool that wasn't compatible even though it said it might have been. Eg: "Universal coolants" used as top-off or for partial drain/fill's instead of Dexcool from GM. Similar happened with Chrysler vehicles and their OAT formulations being mixed with other stuff that shouldn't have been.

I was a tech for a government fleet when this whole Dexcool thing was going on and believe me this didn't happen because of mixing of coolants (at least with us). This happened because of poor engine design. We saw it ALL OF TIME in the GM passenger cars, not so much in the trucks or even the 3.8's, but the smaller V6's...I can't remember what they were...3.4's? Yeah I believe that's what they were. Those intake gaskets were so thin from the factory, they'd just tear, then leak, then they were done. We didn't really blame the Dexcool on it, but YES the Dexcool would sludge up if the system was low and had air in it...it'd sludge up a lot. And yes the Dexcool probably did weaken the little rubber on those intakes and cause them to fail, but the gaskets, those intakes, those engines were poorly designed. The 3.8's? They would fail on the intakes because they ran the EGR tube right through the intake gasket, it'd crack or melt...then it'd fail. The trucks? The 5.3's, the 5.7's? I don't think I ever changed an intake or had a Dexcool problem. But the 3.4's in the Malibu, the Buick Regals, the Pontiac Grand Ams and Grand Prix's, the Impalas...I was replacing one a day. And it went on for years. Now? I have not seen one single coolant issue on a GM vehicle. Other problems, yes, but not coolant related...not big known issues with leaks and poor design. That 3.4 Motor was a nightmare...stuff of legends. They'd click and clank even when they were running "good". The wrist pins in the pistons would be loud upon start up. The lifters would sometimes fail. The EGR systems would clog up. The rear spark plugs were a nightmare to replace. Misfire machines with vacuum leaks, sensor failures, EGR problems, throttle body problems...just a ratty little engine. The weird part is, you'd fix them and they'd just keep on going. I mean as poorly designed as they were, you could fix them and they'd keep on going. But lower intake design was a disaster. They used RTV at the factory to connect the intake to the opposing heads! Then they'd lay this cheap, thin gasket between the head ports and the intake, with push rods wedged right through them. It really was a mess. And they sold a ton of these cheap vehicles...and throw that engine in all of them.

 

[Lubener]

Originally Posted by das_peikko

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.

Hi Merkava!

 

[hardheaded]

Originally Posted by Lubener

Originally Posted by das_peikko

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.

Hi Merkava!

This right here! Crap gaskets were the real problem. It was way cheaper for GM to say it was a Dexcool problem and replace some intake gaskets under warrenty than to say all of these cars with these crappy gasket needed replaceing. And only until you got 36,000 miles on the car. Should have replaced everyone of those gaskets BEFORE they failed no matter how many miles were on the car. Bad engineering and design was the real problem.

 

[cronk]

I'll chime in here, as I have had experience in doing 3 or 4 intake gasket jobs on the notorious gm 3.1/3.4 engine. I believe the issue is mostly due to the poor design of the gaskets. The dexcool may have worstened the issue slightly, but the main problem is the design of the gaskets. I changed intake gaskets on my moms Oldsmobile 3.1, it was the last year they ran conventional green, but it had the new style intake gaskets. The gaskets still failed in the same manner the newer ones with dexcool fail. Only had around 70 or 75k miles if I remember right. Gaskets looked just as crappy from the green conventional coolant car as any I changed from newer dexcool cars. I always used the Felpro ultraseal gaskets that had updated metal frames and thicker rubber sealing rings, and used Permatex "right stuff" silicone to seal the valley. Never had one leak again, regardless of what coolant type was used.