What's so "bad" Dex-Cool? I got my coolant changed out about 10,000 miles ago and they put in Dex-Cool for 25 dollars more saying it was better and then I start hearing that its "bad" stuff. FWIW I have a 1994 Chevrolet Cavalier with a 3.1 v6 with 195,775 miles on it
Dex-Cool?
- Thread starter J_Myler
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I don't think it's bad... I have used it in other vehicles and it worked fine. I think the problem is when people mix regular coolant with dex-cool and it causes some sort of sludge or they run the dex-cool too long and it creates sludge. I haven't had any issues with it when changed properly and neither has my dad who is a mechanic...
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Originally Posted By: J_Myler
What's so "bad" Dex-Cool? I got my coolant changed out about 10,000 miles ago and they put in Dex-Cool for 25 dollars more saying it was better and then I start hearing that its "bad" stuff. FWIW I have a 1994 Chevrolet Cavalier with a 3.1 v6 with 195,775 miles on it
Besides when mixing with an incompatible coolant, problems with Dex-Cool type coolants commonly occur when the cooling system is leaky and when aeration happens. I have been using a Dex-Cool type coolant without any issues in a poorly designed and ultra-fragile German vehicle for the past 12 years.
What's so "bad" Dex-Cool? I got my coolant changed out about 10,000 miles ago and they put in Dex-Cool for 25 dollars more saying it was better and then I start hearing that its "bad" stuff. FWIW I have a 1994 Chevrolet Cavalier with a 3.1 v6 with 195,775 miles on it
Besides when mixing with an incompatible coolant, problems with Dex-Cool type coolants commonly occur when the cooling system is leaky and when aeration happens. I have been using a Dex-Cool type coolant without any issues in a poorly designed and ultra-fragile German vehicle for the past 12 years.
Although a properly maintained Dex-Cool system where there are no leaks where air could get in should be fine why bother when you can fill a system with G-05 antifreeze have it last as long and cool as well with zero risks. You can also consider Peak Global which will mix with any antifreeze and also have none of the risks of Dex-Cool or its clones (antifreeze containing 2-EH).
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I'll get right on it.
My 06 grand prix has 22,000 mile's on it.The radiator is getting flushed out soon.I' am putting in Prestone that is made for all types of cars.Another great G.M. idea by putting anti freeze (dex cool) that turns to sludge.Most likey the intake gasket is going to bite the dust soon.I swear this will be the last car enginered in the USA I'll buy.Also it has a clunking sound in the front suspention,most likely a tie rod end going bad.My 2001 G.P. had tie rods replaced twice.I could see if I abused my vehicles stuff would break.On the other hand my 07 C amary is the best car I ever owned.
Here's why Dexcool is bad, sorry for the same post.
http://www.zillamotorsports.com/DEX/
It destroys intake manifold gaskets and head gaskets. Use it long enough and you'll find out personally.
http://www.zillamotorsports.com/DEX/
It destroys intake manifold gaskets and head gaskets. Use it long enough and you'll find out personally.
zgrider,Today I flushed the cooling system on my wife's 3.8 G.P.You should have seen all the sludge.For only 22,000 miles it was a mess.I replaced it with Prestone (for all color anti freeze).The person at G.M. that said that dex cool can go 100,000 miles should be shown the front door.
Originally Posted By: harley145000
zgrider,Today I flushed the cooling system on my wife's 3.8 G.P.You should have seen all the sludge.For only 22,000 miles it was a mess.I replaced it with Prestone (for all color anti freeze).The person at G.M. that said that dex cool can go 100,000 miles should be shown the front door.
I'm guessing the previous coolant hadn't been flushed properly.
Talking to some coolant chemists here they strongly recommend using an acid based flush when cleaning or converting any coolant system to an OAT inhibitor coolant. (most flushes are alkali not acid based)
zgrider,Today I flushed the cooling system on my wife's 3.8 G.P.You should have seen all the sludge.For only 22,000 miles it was a mess.I replaced it with Prestone (for all color anti freeze).The person at G.M. that said that dex cool can go 100,000 miles should be shown the front door.
I'm guessing the previous coolant hadn't been flushed properly.
Talking to some coolant chemists here they strongly recommend using an acid based flush when cleaning or converting any coolant system to an OAT inhibitor coolant. (most flushes are alkali not acid based)
tdi-rick,it was never flushed,my point was g.m. says it will last 100,000 miles.But after 22,000 miles on the dex cool was turning the cooling system into sludge.That why I flushed it out and put prestone in that is for all makes and models.
I don't think there has been a GM 3.1 or 3.4 that didn't have to have an intake manifold gasket replaced because of Dexcool. I'm sure the gaskets are partly to blame, but not entirely because so many other engines are affected too. My Montana 3.4 had 2 replaced and now the head gaskets are leaking too. My daughter's Monte Carlo 3.1 had one engine fail and the replacement engine needed a gasket 30,000 miles later. Now I only use G-05 and will never go back to Dexcool. Every GM I buy will get drained, flushed and refilled with Chrysler G-05 (orange like Dexcool to keep up warranty appearances)
Originally Posted By: harley145000
tdi-rick,it was never flushed,my point was g.m. says it will last 100,000 miles.But after 22,000 miles on the dex cool was turning the cooling system into sludge.That why I flushed it out and put prestone in that is for all makes and models.
No worries.
I read it as the vehicle had more miles and was running Dex-Cool for the last 22,000.
tdi-rick,it was never flushed,my point was g.m. says it will last 100,000 miles.But after 22,000 miles on the dex cool was turning the cooling system into sludge.That why I flushed it out and put prestone in that is for all makes and models.
No worries.
I read it as the vehicle had more miles and was running Dex-Cool for the last 22,000.
Originally Posted By: SilverC6
Has the 3.1 had the intake maniford gasket replaced yet?
If not, get ready for $600 to $800 worth of Dex-cool lovin'.
I just had my 3.1 repaired a couple of weeks ago.
I don't know but the car has 196,000 miles on it so I'd assume that they have been replaced.
Has the 3.1 had the intake maniford gasket replaced yet?
If not, get ready for $600 to $800 worth of Dex-cool lovin'.
I just had my 3.1 repaired a couple of weeks ago.
I don't know but the car has 196,000 miles on it so I'd assume that they have been replaced.
1999 Grand Am GT, 3.4L....Dex-Cool. At 20k miles, some sludge. Had it flushed and refilled. All was better. At 34k miles, boom, LIM gasket starts leaking badly. Fixed under warr. By the time I sold the car at about 57k, the sludge was returning, even after another flush at 35k.
Next car was a 2004 GTO. Only kept it about 10k miles, but it stayed pretty good looking, coolant wise.
Since then, my VW cars had G12, I believe, my Hyundai had "green" and so does my current Mazda3. Mazda3 is getting ST all makes for drains/refills.
Not a fan of Dex-Cool. My BIL's Tahoe is approaching 50k. I'm going to do some work for him, and I will be flushing and switching to G05 or ST all makes, based on his spending limit.
Maybe Dex is OK, but not in my experiences.
Next car was a 2004 GTO. Only kept it about 10k miles, but it stayed pretty good looking, coolant wise.
Since then, my VW cars had G12, I believe, my Hyundai had "green" and so does my current Mazda3. Mazda3 is getting ST all makes for drains/refills.
Not a fan of Dex-Cool. My BIL's Tahoe is approaching 50k. I'm going to do some work for him, and I will be flushing and switching to G05 or ST all makes, based on his spending limit.
Maybe Dex is OK, but not in my experiences.
From what I have read, DEX-COOL is only bad in GM vehicles, due to the incompatibility with the plastics used in the manifold / gaskets.
DEX-COOL can do quite well in a non-GM vehicle (oh the irony).
Am I correct?
DEX-COOL can do quite well in a non-GM vehicle (oh the irony).
Am I correct?
Originally Posted By: Jonny Z
From what I have read, DEX-COOL is only bad in GM vehicles, due to the incompatibility with the plastics used in the manifold / gaskets.
DEX-COOL can do quite well in a non-GM vehicle (oh the irony).
Am I correct?
Dex-Cool does REALLY well when the cooling system is sealed with no leaks. All the vehicles that have issues have air being introduced into the system, via design flaws. Most of the newer GM vehicles with the pressurized overflow tanks do great. I had my Silverado 5.3 flushed at the 3 year mark (around 35k) and the tech said it looked good and clean, no gunk/sludge at all.
From what I have read, DEX-COOL is only bad in GM vehicles, due to the incompatibility with the plastics used in the manifold / gaskets.
DEX-COOL can do quite well in a non-GM vehicle (oh the irony).
Am I correct?
Dex-Cool does REALLY well when the cooling system is sealed with no leaks. All the vehicles that have issues have air being introduced into the system, via design flaws. Most of the newer GM vehicles with the pressurized overflow tanks do great. I had my Silverado 5.3 flushed at the 3 year mark (around 35k) and the tech said it looked good and clean, no gunk/sludge at all.
for years toyota v6 had serious sludge problems and thousands of those v6 engines were replaced we are rebuilding two of them this week the gm engines are not so bad except for the associated problems with the dex cool.. im not saying we dont see them we do but there are thousands more of the gm v6 on the road.
Originally Posted By: harley145000
tdi-rick,it was never flushed,my point was g.m. says it will last 100,000 miles.But after 22,000 miles on the dex cool was turning the cooling system into sludge.That why I flushed it out and put prestone in that is for all makes and models.
One might guess you put back in a Dex-Clone, which is almost as bad as DexCool. Check if what you put in contains 2-EH, if it does, then its a Dex-Clone.
You want a Zerex G-05 or Peak Global, neither of which has 2-EH. Peak Global even boasts about being non 2-EH.
tdi-rick,it was never flushed,my point was g.m. says it will last 100,000 miles.But after 22,000 miles on the dex cool was turning the cooling system into sludge.That why I flushed it out and put prestone in that is for all makes and models.
One might guess you put back in a Dex-Clone, which is almost as bad as DexCool. Check if what you put in contains 2-EH, if it does, then its a Dex-Clone.
You want a Zerex G-05 or Peak Global, neither of which has 2-EH. Peak Global even boasts about being non 2-EH.
good advice donald,i'll check into it.
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