GM Dexcool
auto trainy
02-06-2005, 12:14 PM
Does anyone Know if GM has done anything about the problems that Dexcool has been causing and if so,what? Thank's
TheSilentChamber
02-06-2005, 02:38 PM
what kind of problems?
MagicRat
02-06-2005, 05:31 PM
Personally, I think this is a maintenance problem. Dexcool is promoted as a very long life coolant..........so people ignore cooling system maintenance until the car breaks. By that time, its too late. Cooling system components have corroded and the system has accumulated excess debris....like any system would if no maintenance was done.
Regardless of what is in the system, a cooling system flush and fill every 2-3 years is good preventive maintenance.
Regardless of what is in the system, a cooling system flush and fill every 2-3 years is good preventive maintenance.
curtis73
02-07-2005, 01:26 AM
Although my information is a little dated, we Impala SS owners have had incredible problems with DexCool. About five years ago I asked about 500 Impala SS owners to relay their exact issues and I compiled the info.
Basically, here is the issue as we see it. First of all, you have to understand what goes on at GM when a vehicle is designed/planned in Detroit. The different departments are set to their tasks. Weekly they meet and discuss and constant communication is maintained either casually (over a few beers after work) or formally (memos, phone calls, etc). In the end 90% of the vehicle's build properties are determined by about 30% of the team. The rest is left to the interns, staff flunkies, and other smaller teams.
With that background... In the case of DexCool, two main problems happened. 1) GM didn't properly read the information that its designer included with they coolant they designed. GM over-rated its life by a considerable amount. It spawned a lawsuit since GM's misrepresentation cost the designer (which I think was havoline) millions. 2) In light of the above paragraph, the 30% of the team making decisions about the cars didn't listen to the 70% interns and flunkies when they recommended against the clay tablets in the coolant. GM made it a policy to include clay tablets in every car's cooling system. The idea was that the inexpensive clay tablets and their dissolved silicates help to plug leaks. They are highly ineffective, but if it masks a leak for 5 extra miles which takes the car out of warranty, it has paid for itself a million times over. The clay tablets that GM used for decades didn't mix well with the DexCool. It causes silicates to precipiate out of suspension and you basically have sandy water in your cooling system. We SS owners for several years called it "orange jello" since thats what it very closely resembled.
As of 1998, GM had done nothing. They continued to put clay tablets in with DexCool despite millions of consumers, flunkies, interns, and Mr. Goodwrenches screaming at GM. It was such big business and Dexcool was such a small thing that it was about as important as a hangnail is to a boxer. Everyone was screaming, "dexcool, dexcool!" but all GM execs heard was "blah blah, blah blah!" Classic case of the left hand not knowing what the right hand was doing.
Since 1998, I'm not sure what they've done, but there are TSBs at these websites....
http://www.tsbdata.com/
http://www.alldata.tsb.com/
... Or do a search for "auto tsb", pick any one of the many TSB publishing pages and do a search for "dexcool." You'll come up with far more than I can remember from so many years ago. Keep in mind that many TSBs are based on thousands of service calls where the consumer has figured out something long before the manufacturer has, so the TSBs might be behind the times despite their date of issue :)
Basically, here is the issue as we see it. First of all, you have to understand what goes on at GM when a vehicle is designed/planned in Detroit. The different departments are set to their tasks. Weekly they meet and discuss and constant communication is maintained either casually (over a few beers after work) or formally (memos, phone calls, etc). In the end 90% of the vehicle's build properties are determined by about 30% of the team. The rest is left to the interns, staff flunkies, and other smaller teams.
With that background... In the case of DexCool, two main problems happened. 1) GM didn't properly read the information that its designer included with they coolant they designed. GM over-rated its life by a considerable amount. It spawned a lawsuit since GM's misrepresentation cost the designer (which I think was havoline) millions. 2) In light of the above paragraph, the 30% of the team making decisions about the cars didn't listen to the 70% interns and flunkies when they recommended against the clay tablets in the coolant. GM made it a policy to include clay tablets in every car's cooling system. The idea was that the inexpensive clay tablets and their dissolved silicates help to plug leaks. They are highly ineffective, but if it masks a leak for 5 extra miles which takes the car out of warranty, it has paid for itself a million times over. The clay tablets that GM used for decades didn't mix well with the DexCool. It causes silicates to precipiate out of suspension and you basically have sandy water in your cooling system. We SS owners for several years called it "orange jello" since thats what it very closely resembled.
As of 1998, GM had done nothing. They continued to put clay tablets in with DexCool despite millions of consumers, flunkies, interns, and Mr. Goodwrenches screaming at GM. It was such big business and Dexcool was such a small thing that it was about as important as a hangnail is to a boxer. Everyone was screaming, "dexcool, dexcool!" but all GM execs heard was "blah blah, blah blah!" Classic case of the left hand not knowing what the right hand was doing.
Since 1998, I'm not sure what they've done, but there are TSBs at these websites....
http://www.tsbdata.com/
http://www.alldata.tsb.com/
... Or do a search for "auto tsb", pick any one of the many TSB publishing pages and do a search for "dexcool." You'll come up with far more than I can remember from so many years ago. Keep in mind that many TSBs are based on thousands of service calls where the consumer has figured out something long before the manufacturer has, so the TSBs might be behind the times despite their date of issue :)
auto trainy
02-07-2005, 05:33 AM
Thank's Curtis that explains a lot.What have you SS owners done as a substitute? My friend works at a dealership and he told me of newer cars with gasket problems caused by Dexcool,(high end cars)
I have a 98 olds with Dexcool in it and I am concerned, thank's again
I have a 98 olds with Dexcool in it and I am concerned, thank's again
tom3
02-07-2005, 08:28 AM
Generally you just need to shine a flashlight down into your radiator every month or so. If the coolant looks decent and the level is staying up, you have no problem. If it is murky or, heaven forbid, muddy looking, you have the beginnings of a major problem. If you're losing coolant the Dexcool or the engine design has your intake manifold gaskets leaking. The jury is out on which causes this I think. The Dexcool is primarily designed to keep owners out from under the hood until the warranty is up, then when problems develop, its your nickel. My suggestion is to get the Dexcool out, replace with the new long life Prestone that's available about everywhere.
curtis73
02-07-2005, 02:07 PM
Thank's Curtis that explains a lot.What have you SS owners done as a substitute? My friend works at a dealership and he told me of newer cars with gasket problems caused by Dexcool,(high end cars)
I have a 98 olds with Dexcool in it and I am concerned, thank's again
We lose our heaters to the jello. When that happens we flush twice and refill with 50/50 green coolant. Both the dexcool and regular green are ethylene glycol based so they offer the same protection against corrosion, they have the same thermal properties, and lubrication. The additives in the two are different, so make sure you adequately flush before introducing the green coolant. They aren't compatible.
The perplexing thing is that the dexcool doesn't have really anything different from the green stuff, and because of its issues, the dex tends to not last as long as the green.
Some owners have had luck refilling with new 50/50 dex and not including the clay tablets. Others have had recurrent issues. Silicates are pretty easily coaxed out of suspension in Dexcool and any residual clay I'm convinced will allow precipitation of the stuff.
I have a 98 olds with Dexcool in it and I am concerned, thank's again
We lose our heaters to the jello. When that happens we flush twice and refill with 50/50 green coolant. Both the dexcool and regular green are ethylene glycol based so they offer the same protection against corrosion, they have the same thermal properties, and lubrication. The additives in the two are different, so make sure you adequately flush before introducing the green coolant. They aren't compatible.
The perplexing thing is that the dexcool doesn't have really anything different from the green stuff, and because of its issues, the dex tends to not last as long as the green.
Some owners have had luck refilling with new 50/50 dex and not including the clay tablets. Others have had recurrent issues. Silicates are pretty easily coaxed out of suspension in Dexcool and any residual clay I'm convinced will allow precipitation of the stuff.
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