jds68stang

I did just basic research last year and found 3 types.

IAT: (inorganic additive technology) ,traditional green used in older cars, that needs change yearly.

OAT: (organic acid technology) aka Dex-Cool for newer GMs, extended life.

HOAT: (hybrid organic acid technology) found in newer Ford, Chrysler, Mercedes, extended life.

I've heard the (OAT- Dex- Cool) will eat into gaskets if put into an older car, anyone have knowledge on that if true or not? Also w/ the Dex-Cool I'm aware it will sludge up your systen quick should any air get into the system.
GM was sued over Dex-Cool and paid out to parties that could show gasket failure up to I believe 1995, but I still see it on the market and apparently still more suits pending.

Also been told all Prestones are Dex-Cool clones if the ingredients are checked and matched against Dex-Cools.

Now I see an anti freeze mix that says its OK to add to any other type, kind of getting confusing.
What are you guys running w/ an old block w/ updated aluminum radiator or aluminum heads?

Also heard some of the newer will eat into the lead on older radiators.
Here's one link about GMs Dex-Cool troubles.
http://www.autoblog.com/2006/05/23/g...action-status/

rihwoods

Ok ...this is no BS...I run Prestone 50/50 in both vettes...the 78 has alum rad...the 69 502 has CB rad,alum heads,etc...

That is my story,and I'm sticking to it...

RIJVETTES

The old fashioned Green stuff- 33-50%, with plain tap or distilled water. Changed about every 2 years. in warm San Diego. Rebuilt 355, with a stock replacement radiator and aluminum heads.

Durango_Boy

The new Prestone Yellow is the berries. I mix it with distilled water for use in my DeWitts. I use a bit more water than coolant, because it gets warm here in the summers, but the Prestone Yellow is a fantastic new coolant good for any make, model, or year.

GD70

Same here. Always runs cool. Hottest it's ever gotten is 210 on a 95 degree summer day. Consistantly runs 170-180.

capevettes

Run the GREEN STUFFF in the older cars. Mix it 50/50 with distilled water. It does not need to be changed every year. I do mine every 3 years or whenever the heater core blows whichever comes first. Car Quest's generic green stuff is fine.

Ak. Mal

The orange Dex-Cool can NOT be mixed with the green. They crystallize if put together. I ran Dex-Cool in my '96 K1500. That stuff was crap. Don't ever use it if you can avoid it. I don't even want to discuss how many gaskets I had to change.

I run the good ol' green stuff and I'm never switching.

jds68stang

Just found this link dated 3/20/08, court decision against GM for Dex-Cool.
It might help you recover damages if any of you had gasket problems and still have the repair reciepts on your GM.
My intake just went on my Silverado, no doubt from that Dex-Cool crap

I'm going to get that out of GFs Blazer ASAP and run the G-05 Ford/Chrysler extended life, no problems reported w/ that so far.
Seems some of the Prestones are very similar to the Dex-Cool, do some research if your running that or Texacos's anti freeze.

http://www.girardgibbs.com/dexcool.html

thrilher

As an avid motorcyclist i've had watercooled motorcycles since late 70's. These motorcycles have alot of interior aluminum and other sensitive corrosive metals.The manufacturers recommended a ethylene glycol based antifreeze and distilled water ONLY in 50/50 solution.I personally chose Texaco "green" antifreeze and applied that to every vehicle i've ever owned then & since and never once had radiator or rust problems with anything.I still use that to this day. The only blemish i've seen at all is a green residue build at the bottom of the overflow tank.Got an '84 motorcycle and a '90 truck and no problems whatsoever in all these years.I at times went over 5 yrs w/o changing these fluids but i do live in a warm climate.
Dexcool,when it became difficult to find regular ethylene glycol based antifreeze i checked into this new stuff.After some research i found it to be worthless.The problem is, the coolant supposedly works fine as long as the radiator is topped off full.If it falls below full their is a crust that builds "almost like calcium" and it eventually will clog up the tubes in the radiator cutting off circulation.
Supposedly with newer vehicles their are materials used that some of the older antifreezes will harm, that is what i was told.Kinda skeptical of that statement myself.Any vehicle built after 1993 is garbage anyway in my opinion so i won't be purchasing anything built after that year so that eliminates the possible problem of engine damage due to improper antifreeze for me.With your C3 the green will be just fine.
Just keep in mind distilled water has no minerals to create deposits while tap water contains many.I think that is probably a key factor in my success.For the record, in the 70's when i was looking at different antifreezes prestone and most other green antifreezes weren't ethylene glycol based.Read the label

68/70Vette

What did they use? I thought the green stuff was pure ethylene glycol plus some silicate additives.

rihwoods

I flush once a year,regardless...

TEXASDESERTVETTE

Distilled Water with a little bit of Tide Laundry Soap added (for a wetting agent) for lubrication to the pump seal.

rihwoods

Bubble bath...

jds68stang

GF found this post on a blazer forum written by BTJUSTICE, I read his info last year on a stang forum, has a lot of links and is informative but lengthy. Also I gave a Dex-Cool link after his post to show what happens w/ this crap in your system if any air gets in.


Heres his post from the blazer forum:

I came across this thread during a web search. After reading all of it in its entirety, I had to register just to share a few things...

Dex-Cool is ethylene glycol (EG) coolant just like G-05, old-type green coolant (what Prestone use to make), and new-type green coolant (what Zerex green is which has lower silicate levels than the old Prestone coolant). Japanese coolant is also EG. Prestone did make a propylene glycol (PG) coolant, but it is not all that much better for the environment than EG. PG doesn't work any better than EG or vice versa.

Old-type green and new-type green coolants are EG IAT (inorganic additive technology) coolants. Old-type green had a heavy load of phosphates and silicates. Even if you could find old-type green, I would STRONGLY recommend not using it as a Dex-Cool replacement. Zerex has improved it by using less silicates and increasing its service life to 5 years/100,000 miles (which I call new-type green). The new-type green is an excellent replacement for Dex-Cool.

Dex-Cool is an EG OAT (organic acid technology) coolant. It contains no phosphates and no silicates.

G-05 is an EG HOAT (hybrid organic acid technology) coolant. It is somewhat similar to Dex-Cool but it differs in some of the inhibitors used and that is contains silicates. The silicates make it a hybrid.

Most Japanese coolants are also EG HOAT but use phosphates instead of silicates.

The green Prestone All Makes All Models, the green Wal-Mart SuperTech, and the Peak Global coolants are all formulated EXACTLY like Dex-Cool. The reason they don't advertise as Dex-Cool is to bypass the licensing fees they would have to pay to GM. In order to do this, they are dyed green, gold, and other colors.

Dex-Cool does eat gaskets. One of its ingredients is 2-Ethylhexanoic Acid (aka 2-EHA) which is a plastic softener. A study confirmed Dex-Cool eats silicone and nylon...

http://www.imcool.com/articles/antif...l2007Part3.php

"Those companies included heavy duty manufacturers Caterpillar, Cummins and International. He authored two technical papers, derived from thousands of hours of testing, focusing on the effects that DEX’s corrosion inhibitors have on rubber and plastic gaskets and seals, including GM’s IMGs in question. He concludes that the two are incompatible because DEX OAT inhibitors degrade both silicone and nylon, of which these gaskets are made."

The above link also has information on the class action lawsuit against GM in regards to Dex-Cool which is now happening is Missouri.

The old-type green coolant Prestone use to make is no longer made and cannot be found in stores. THANKFULLY, Zerex makes a new-type green coolant which has a lower amount of silicates so it is ideal for both automotive and diesel applications. The new Zerex green coolant also lasts 5 years/100,000 miles...

http://www.valvoline.com/pages/produ....asp?product=8
http://www.valvoline.com/products/zerexoriginal.pdf

Shell also makes a green coolant that sounds like it is similar to the new Zerex green coolant, but I cannot find any info on it in regards to how long it lasts...

http://www.shell.com/home/page/us-en..._products.html (This is for the pre-diluted version)
http://www.shellusserver.com/products/pdf/Shellzone.pdf

Zerex also makes G-05 which is what Ford and Chrysler have been using for the last few years. John Deere has used it for a long time and even recommends using it in equipment going back many years. Mercedes-Benz has also used G-05 for a long time now...

http://www.valvoline.com/pages/produ...asp?product=10
http://www.valvoline.com/products/zerexg05.pdf
http://www.deere.com/en_US/parts/par..._coolgard.html

Ford G-05 is gold, Chrysler G-05 is red, John Deere G-05 is green, and I am not sure what color Mercedes-Benz uses.

G-05 can be used instead of real green coolant. It is really your choice between real green coolant (Zerex) or G-05. I usually use Zerex green in everything I own as it is easy to find in my area. I personally will not use Dex-Cool.

Here are some pictures of Dex-Cool mud/slime from a car I worked on a few years ago. I converted it to the Zerex green coolant and it has no problems since...

http://www.freewebs.com/btjustice/pi...2003%20001.jpg
http://www.freewebs.com/btjustice/pi...2003%20002.jpg

I have yet to see the new-type green and G-05 coolants do what Dex-Cool did to the cooling system pictured above.

I cannot argue against the fact that the vast majority of GM vehicles with Dex-Cool have never had problems from it, but those who have do get the mud and/or leaks. I believe the mud forms when air gets into the cooling system when it is run too low and forms rust. The rust circulates in the cooling system and causes more problems.

It is also interesting to note that particulate matter seems to float at the top of the radiator in Dex-Cool systems but sinks to the bottom of the radiator in G-05 and in real green coolant systems.

I also think there are design flaws in most GM cooling systems. Plastic crappy head gaskets and crappy radiator caps have already been mentioned. But also the overflow tank is poorly designed. The lowest point of the overflow tank (which should be pressurized BTW with a pressurized cap and be connected to the radiator with a bigger rubber hose that has no cap on the radiator) should be higher than the highest point in the rest of the cooling system. This insures the cooling system is truly full and gets most of the air out of the cooling system. Yet GM continues to use unpressurized overflow tanks that sit lower than the top of the radiator. The overflow tank can show a properly filled level but the radiator can still be very low on coolant. The radiator neck the radiator cap connects to also stupidly sits at an angle. This angle is why the original radiator caps don't seal correctly if they become clogged which is easy to happen when positioned at a angle. The Stant replacement has a spring which pretty much corrects this but it is not perfect. The neck should be straight up and down if GM continues to use it, but they should really move on to a pressurized overflow tank.

So if you want to abandon Dex-Cool, the Zerex new-type green coolant is an excellent choice. G-05 will also work.

No matter what coolant you run, keep on eye on the levels both in the overflow and the radiator! This is YOUR responsibilty.

I personally like to drain both the overflow tank and radiator once every year and fill them back up with a fresh mix of coolant (55-60%) to distilled water (40-45%). This gets any possible dirt out of the overflow tank and radiator and keeps the coolant nice and fresh so a complete cooling system flush is not needed. This also keeps the coolant at a proper PH level.

Never use city or well water!!! City water contains haloacetic acids, trihalomethanes, chlorine, barium, chromium, fluoride, nitrate, selenium, and sodium. Well water has even more crap in it. This is why scale forms in cooling systems. USE DISTILLED WATER!!! De-ioned water and de-mineralized water are also considered to be distilled.

Hopefully Helpful,
BTJustice

< Message edited by BTJustice -- 12/4/2007 6:12:53 AM >

Pics of the sludge from Dex-Cool:
http://www.sancarlosradiator.com/dex-cool_pics.htm

Glassbowtie77

Same here.

Durango_Boy

I know you mention the Prestone Green above, but the new stuff I have been using is Prestone Yellow. Is it also formulated like Dex-Cool?

L82shark

Guess I had my head stuck in the sand..... I had never heard of the Dexcool issues before, just changed the fluids in 4 of my cars just a couple of months ago and refilled with Dexcool. Know what I will be doing this weekend now.

Not to change the topic, but what is the best way to flush the system? I used to shove a waterhose down its throat.....

Good info to know tho......

jds68stang

I just read more of BTJUSTICE's posts now and he says it IS the same and says he's been educating himself on this for 10 years now. Here's the link for the full thread on the blazer forum, he has 2 posts.
http://www.blazerforum.com/m_21318/mpage_6/key_/tm.htm

I put Prestone in my 68 mustang w/ an old leaded radiator before I knew better so thats another job now and that block and rad. was clean as new inside prior, better still be. Like L82shark, I got 3 GM's to flush ect... plus now a IMG I have to replace on my truck!, I'm pissed to say the least.
(don't they have a flipping the bird smiley for GM here )

L82shark, be sure to get it all out of the heater core as well, each vehicle is different to drain and one of those lines should be unhooked to drain and flush fully out. No need to do them all at once just keep the levels up till you change them. Like BTJs post said use the final fill and flush w/ distilled or demineralized water then refill w/ new coolant.


There is a 4th type of anti freeze w/ out any of these problems and racers use it but I can't recall what it was called and can't find the link yet, expensive but cheaper than replacing a IMG. Will post it if I can find it.

Durango_Boy

So the Zerex New Green is the way to go, with distilled water in a DeWitts Aluminum radiator?

L82shark

I am going to look for the G-05 on the bottle.....