DEX COOL Problems?
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Melting Slicks
Joined: Aug 1999
Posts: 2,619
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From: Whidbey Island Washington
DEX COOL Problems?
How many of you had proplems with DEX-COOL in your Vettes or other GM motors? I understand Girard Gibbs & DeBartolomeo law firm is investigating claims in connection with a proposed class action against GM & Cheveron/Texaco concerning DEX-COOL. I've not had problems with any of my Vettes (YET) but have serious problems with our '98 Cadillac after ONLY 64K miles because DEX-COOL FORMED A SLUDGE-LIKE SUBSTANCE THAT CLOGED THE COOLING SYSTEM CAUSING IT TO OVERHEAT. I also understand the class action findings include DEX-COOL corroding all parts of the engine it comes in contact with including heater core, water pump, hoses, cap, upper and lower intake mainfold, theremostat and engine block. How would I flush DEX-COOL from my '96 CE? A local Chev dealer charges $700 for a cooling system flush with special flushing equipment and then ONLY reinstalls DEX-COOL!
Race Director
Joined: Oct 2000
Posts: 14,060
Likes: 1,165
From: N. Alabama
No problems with the '96. I have drained the cooling system once and put in the Dex-cool again. I now have 90K on her.
Also, I put the Dexcool in my restored '81 Mercedes about 3 years ago. I had drained the block, heater core and radiator. No problems 25k later.
I believe the problem may be in the mixing of 2 and 5 year stuff in some instances, other problems may be vehicle model particular. Make sure all coolant is drained when refreshing and/or changing to 5 year.YMMV.
Also, I put the Dexcool in my restored '81 Mercedes about 3 years ago. I had drained the block, heater core and radiator. No problems 25k later.
I believe the problem may be in the mixing of 2 and 5 year stuff in some instances, other problems may be vehicle model particular. Make sure all coolant is drained when refreshing and/or changing to 5 year.YMMV.
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
No problem....
I have a 1996 with 83000 miles and use Dex-cool. I did a flush last month and replaced the red (blush) Dex-cool and runs just fine. Still runs cool.....On the highway: 189 In traffic: 194. My .02
Drifting
Joined: Nov 2002
Posts: 1,593
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From: Mobile AL
St. Jude Donor '05
My '96 CE has been drained and refilled (with DEXCOOL). There was no sludge, and I've had no problems. Got 93K miles. My '96 Olds 88LS has over 100K, has been flushed and refilled, and no problems with it, either. I have not heard of any issues about the stuff. It may have to do with that "pill" that some folks insist must be put in there.
Team Owner
Joined: Sep 2003
Posts: 88,393
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From: eville in
Originally Posted by ZRWON
How many of you had proplems with DEX-COOL in your Vettes or other GM motors? I understand Girard Gibbs & DeBartolomeo law firm is investigating claims in connection with a proposed class action against GM & Cheveron/Texaco concerning DEX-COOL. I've not had problems with any of my Vettes (YET) but have serious problems with our '98 Cadillac after ONLY 64K miles because DEX-COOL FORMED A SLUDGE-LIKE SUBSTANCE THAT CLOGED THE COOLING SYSTEM CAUSING IT TO OVERHEAT. I also understand the class action findings include DEX-COOL corroding all parts of the engine it comes in contact with including heater core, water pump, hoses, cap, upper and lower intake mainfold, theremostat and engine block. How would I flush DEX-COOL from my '96 CE? A local Chev dealer charges $700 for a cooling system flush with special flushing equipment and then ONLY reinstalls DEX-COOL!
Race Director
Joined: Sep 2004
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
I am good friends with several mechanics. 2 are GM mechanics. I have seen (personally) several instances where the Dex-cool has severely damaged the cooling system. If the owner does not maintain the system, the Dex-cool will break down and build up in various spots in the system and cause major blockage. From what I understand, once your cooling system gets contaminated with this, the whole system needs to be replaced. I personally find that hard to believe, but I'm not a certified mechanic.
I changed mine to the green stuff, but was told that the green stuff will cause the internal damage that you listed above. The Dex-cool is far superior, but like an oil change it must be serviced regularly. The GM mechanic friend recommended a full flush and fill every 20k miles. If properly maintained, there will not be any problems, but the cooling system is the most neglected part of every vehicle.
I changed mine to the green stuff, but was told that the green stuff will cause the internal damage that you listed above. The Dex-cool is far superior, but like an oil change it must be serviced regularly. The GM mechanic friend recommended a full flush and fill every 20k miles. If properly maintained, there will not be any problems, but the cooling system is the most neglected part of every vehicle.
Melting Slicks
Joined: Jan 2000
Posts: 3,418
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From: NW Chicago Suburbs
It's the pellets, don't use 'em and you won't have any problems. GM no longer recommends them, but most dealership mechanics can't get out of the habit.
$700 for a coolant flush, this dealer is shameless!
Eric
$700 for a coolant flush, this dealer is shameless!
Eric
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Race Director
Joined: May 2001
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The idea of having to service a dexcool system every 20k miles is sad, that defeats the entire purpose of the product. Any new vehicle that comes with dex-cool and only runs dex-cool will continue to work just fine at the recommended interval.
The "sludge" comes into play when you mix dex-cool with conventional anti-freeze. Mixing the two also creates an acid which tears at all the engine parts. If you completely flush your cooling system and switch to dex-cool you will have no problems. If you just half *** it and try to switch over you're asking for trouble. Furthermore if you accidentally mix the two in a new car you'll have problems.
Either product works very well by itself. If you mix them you're in trouble.
The "sludge" comes into play when you mix dex-cool with conventional anti-freeze. Mixing the two also creates an acid which tears at all the engine parts. If you completely flush your cooling system and switch to dex-cool you will have no problems. If you just half *** it and try to switch over you're asking for trouble. Furthermore if you accidentally mix the two in a new car you'll have problems.
Either product works very well by itself. If you mix them you're in trouble.
Team Owner
Joined: Oct 2000
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From: Fort Knox, KY
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Originally Posted by silver & red CE
It's the pellets, don't use 'em and you won't have any problems. GM no longer recommends them, but most dealership mechanics can't get out of the habit.
$700 for a coolant flush, this dealer is shameless!
Eric
$700 for a coolant flush, this dealer is shameless!
Eric
Race Director
Joined: Mar 1999
Posts: 16,950
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From: Stafford, Virginia Kittah, Kittah, Kittah...
No problems with either 96 Vette, or with my 98 Caddy...
One of my friends is a certified GM mechanic and he also tried to get me to swich my cars over to the older green stuff... He mentioned the same problems you did, but I've never had any bad experiences...
My friend did mention to me that you usually don't have problems when you maintain the vehicles properly... He sees me under the hood all the time so he laughs at how I overmaintain my vehicles...
One of my friends is a certified GM mechanic and he also tried to get me to swich my cars over to the older green stuff... He mentioned the same problems you did, but I've never had any bad experiences...
My friend did mention to me that you usually don't have problems when you maintain the vehicles properly... He sees me under the hood all the time so he laughs at how I overmaintain my vehicles...
Melting Slicks
Joined: Nov 2003
Posts: 3,375
Likes: 1
From: Northern CA
I have been reading about Dex Cool problems for some time. It sounds like the major cause of Dexcool probplems is air in the cooling system. You need to keep your cooling system in good condition.
You also need to check to see that the fill tank is full, not just the overflow resevoir. Take the pressure cap off and check the fill tank once a week or more when the engine is cool. It is possible to get low coolant level in the engine while the overflow tank level is still good.
Prestone "Dexcool Approved" (not actually Dex Cool) may also cause less problems, it has slightl'y different chemestry. The jury is still out.
You also need to check to see that the fill tank is full, not just the overflow resevoir. Take the pressure cap off and check the fill tank once a week or more when the engine is cool. It is possible to get low coolant level in the engine while the overflow tank level is still good.
Prestone "Dexcool Approved" (not actually Dex Cool) may also cause less problems, it has slightl'y different chemestry. The jury is still out.
Melting Slicks
Joined: Jan 2000
Posts: 3,418
Likes: 1
From: NW Chicago Suburbs
Originally Posted by onedef92
When you say the pellets, do you mean the pellets with Dex-Cool or the pellets with the green coolant? Or are you saying NO ONE should use the pellets anymore period?
Eric
