is Dex Cool bad?

Status
Not open for further replies.
Joined
Jun 24, 2007
Messages
348
Location
TN
We have a new car and I was wondering if there is any significant evidence that Dexcool is bad. If so, can I just change to the green without any problems. My last GM vehicle (2002 Silverado) used dex cool and it has over 150k on the clock without any issues at all. Just curious.
 
From what I've heard, dexcool is fine as long as it is properly maintained.
 
I have read copious information on Dexcool and my conclusion is that it is an excellent antifreeze when used in motors where it makes no contact with the i/m gaskets. In motors where it contacts the i/m gaskets it tends to degrade them. This is beecause of the 2-EHA which is a 'plasticizer'.
The GM 3.1 and 3.4 V6's suffered from a poor design (not enough fasteners and an OE gasket w/o a metal rim) PLUS the degradation caused by Dexcool. The combination virtually guaranteed i/m gasket failure with coolant leaking into the oil.
 
I have the LQ4 6.0L in an 05 vehicle. Which category does it fall under?
 
Our Saturn has Dexcool. Never had any issues with it. I change it about once every 3 years or so, and it's always looked as clean as a whistle.
 
Originally Posted By: pbm
I have read copious information on Dexcool and my conclusion is that it is an excellent antifreeze when used in motors where it makes no contact with the i/m gaskets. In motors where it contacts the i/m gaskets it tends to degrade them. This is beecause of the 2-EHA which is a 'plasticizer'.
The GM 3.1 and 3.4 V6's suffered from a poor design (not enough fasteners and an OE gasket w/o a metal rim) PLUS the degradation caused by Dexcool. The combination virtually guaranteed i/m gasket failure with coolant leaking into the oil.


Thanks for at least thinking about it. At least you didn't just join the chorus of haters, you did some research!
 
Like I have said before. Dex cool is like smoking, when your smoking it and it doesnt cause cancer it feels great! But when it causes cancer it really sucks.

Green is safe if dexcool is properly flushed.

remember its a problem on the 4.3ls too.
 
Last edited:
Originally Posted By: defektes
Like I have said before. Dex cool is like smoking, when your smoking it and it doesnt cause cancer it feels great! But when it causes cancer it really sucks.


I don't think smoking is a very good analogy. A sharp knife would be a better analogy. A sharp knife will cut you badly if you are careless. Dexcool-equipped systems will have major problems if neglected, but as long as you do not have a vehicle with the IMG problems and you maintain the cooling system, Dexcool works beautifully.
 
What kind of car is it? Outside of Dexcool alledgedly being a plasticizer, and you have to figure by now they know about that and aren't using any Dex-cool incompatible gaskets at this point, and being intolerant to air, Dexcool does protect very well. It's important to have the pressure cap on the overflow reservior and at the highest point or air will get into the system and cause problems with dexcool. Does your car have a pressurized reservior? If so then Dexcool works great.
 
Originally Posted By: mechanicx
What kind of car is it? Outside of Dexcool alledgedly being a plasticizer,


It's not alleged. Ford tested Dexcool and found it softens plastics. That's why they went with GO5. 2EHA organic acid is a know plasticizer.

http://www.imcool.com/articles/antifreeze-coolant/dexcool2007Part2-draft.htm

A Dex clone was factory fill in the 99 Cougar.

"Paul went on to document that Ford had used a formula similar to DEX in the '99 Cougar Duratec V6 (DEX is still the coolant of record). However, after noticing gasket distortion and leakage problems in tests for their V8 engines, they dropped DEX-COOL from consideration for additional applications."
 
Last edited:
Originally Posted By: Drew99GT
Originally Posted By: mechanicx
What kind of car is it? Outside of Dexcool alledgedly being a plasticizer,


It's not alleged. Ford tested Dexcool and found it softens plastics. That's why they went with GO5. 2EHA organic acid is a know plasticizer.

http://www.imcool.com/articles/antifreeze-coolant/dexcool2007Part2-draft.htm

A Dex clone was factory fill in the 99 Cougar.

"Paul went on to document that Ford had used a formula similar to DEX in the '99 Cougar Duratec V6 (DEX is still the coolant of record). However, after noticing gasket distortion and leakage problems in tests for their V8 engines, they dropped DEX-COOL from consideration for additional applications."


I didn't mean to suggestion that Dexcool isn't a plasticizer. I was meaning that it gets allegeded to be a plastic gasket eater where the gaskets used are Dexcool compatible. Assuming the automaker made sure that the gaskets are compatible, air is really the only concern and if you have a pressurized coolant reservior Dexcool gives good protection with no issue. I can understand people without a pressurized reservior being leary, or if you don't trust the gaskets to truely be inert to Dexcool.
 
My 98 Chevy PU with the 350 lost the IM gasket after about 4.5 years. Lost the water pump a few years later too. Cant say if the Dexcool caused it or not, but I'm still running it. Might consider changing soon though after finding BITOG.

Andy
 
I've been using Dex-cool in my 1993 Ford Escort ever since the first or second coolant change, and until the last change, it was the Texaco Havoline version (now Prestone -- by the way, Prestone has a buy one, get a rebate on the second offer on all their coolants). I replace Dex-cool every five years.
 
Although there have been some cases where Dex-Cool is a problem, there are more cases where Dex-Cool functioned beyond specification. I have had a lot of problems with Dex-Cool in my 2001 5.3 GM engine. I had a 6 year warranty, so I did not change over to green coolant, but I did do 4 clean, flush, and re-fills in the 6 year period with Dex-cool. I now run the Propylene Glycol coolant. So far, so good. I think the problem with Dex-Cool is air ingestion.
 
Status
Not open for further replies.
Back
Top