While were on the subject of aluminum and plastic radiators, I have a great bit of information I will share. I was talking to my local neighborhood mechanic (the guy I take it to when I can't fix it). He attended a class on the new Dex-Cool anti-freeze. He gave me the scoop for anyone who cares. The green stuff (hereafter referred to as the green stuff) attacks aluminum as it breaks down. The Orange stuff (hereafter referred to as the orange stuff) attacks the plastic as it breaks down. I saw fit to run the Orange stuff, since I'm using all-aluminum rad. So, if the orange stuff breaks down, it won't harm the radiator. Makes sense to me.....

 

In my opinion, Dex-Cool (the orange stuff) eats gaskets and causes more problems than it is worth. But don't expect GM to admit it. Do yourself a favor and stick with green antifreeze.

Take your pick:

http://www.consumeraffairs.com/autom...m_dexcool.html

http://www.dexcoolcase.com/

http://www.automotiveforums.com/t129639.html

 

What about the red stuff?

 

Will the brown stuff still work?

If you switch from one coolant to the other you should flush completely. You shouldnt have the green stuff in there long enough to have it breakdown. Change it and flush it occasionally.

 

Dexcool is an OAT, or organic acid technology coolant. Contrary to what you read it is far superior to traditional coolants in the sense that it is relatively benign to metal components and does not suffer the rather rapid detioration ethlyne glycol based coolants do. The bantering about it is usually caused by talk with no scientific fact to back it up. Usually the problems with it when converting come from the flushing process rather than the the coolant itself. The plastic in the rad tanks will not be broken down by the coolant, the plastic is weakened by the constant temp changes and by the normal breakdown all plastics are subject to. The only real problem with Dexcool comes from too much water dilution or from overheating of the coolant from low level. Dex will turn a muddy color under these conditions and GM recommends a chemical flush when this occurs. Also, many people don't realize that they need to use either GM sealing tablets or the powdered Bars Leak after a flush when changing coolant or converting. I converted my 89 IROC when Dex first came out and had no problems whatsoever. As far as the gasket issue, on older cars that already have gasket issues any flush or change can and most likely will cause problems. When doing a change to Dex you need to do 2 flushes. Do a chemical flush first, add the sealer and run it a week. Then drain the system flush it again with water then add the sealer again and you will be set.

 

My "bantering about it" is caused by years of servicing GM's Dex-Cool equipped vehicles. The links I posted are simply examples.

 

And still the best COOLING I've ever had in my Dirt track engines is straight water with a wetter water or hyperlube,just add some water pump lube and go,go figure.

 

Straight water does the best job for cooling. However, in a street driven car this isn't practical. There are two main reasons we run Coolant/Antifreeze in our cars:
1) To protect the metal parts from rust and corrosion.

2) To increase the boiling point and decrease the freezing point.

 

Well, Dex-Cool is still ethylene glycol based and it will mix with traditional green coolant. It's only the corrosion protection that is different between the two. BUT, by mixing the two coolants you basically ruin the better metal protection Dex-Cool offers.

While some people haven't had any trouble, there have also been numerous problems with Dex-Cool. The exact cause for the "orange mud" is unknown. I have read quite a bit about Dex-Cool online and one idea is that air (any air) in the system may be the cause.

I have also read that Dex-Cool may not last the advertised 5yr/50,000mile lifespan. Some experts recommend changing Dex-Cool every couple years just like traditional green coolant.

I ran Dex-Cool for a time in my GTA without any problems, but recently switched back to the green coolant. During the change-over, I found a small amount of the orange crud in the overflow tank. I also have a '96 Cadillac using Dex-Cool that has the recovery tank coated with the orange residue.
I won't go back to Dex-Cool after my research and seeing the hints of potential trouble in my well maintained car.

Last, have you seen the "new" Prestone Universal coolant? It its supposed to be able to mix with ANY type of coolant. Makes me think the coolant manufacturers are quietly trying to walk away from Dex-Cool in favor of something better.

 

Yes, you are correct, and I should have made that clear that it is still ethylene glycol, the OAT's neutralize the acids that cause corrosion, especially with aluminum components. GM addressed this primarily because of the reduced efficiency that corrosion into these components causes. Using an OAT coolant in the long run will greatly improve the systems cooling capability over the long haul. In a properly operating system it will perform over an extended cycle as opposed to conventional green coolant. Who likes messing with coolant anyway.

 

I believe another factor is the water that is being used to mix with the dex-cool. I work at a GM dealer and have talked to a couple people about this and have come to the conclusion if you want this stuff in your car and want it to last without problems you must mantain it very well, for example if you use regular tap water to mix with it the stuff breaks down and turns into the mudlike substance even faster because of the chemicals used in some areas to purify the water. I also know for a fact that air has an effect on it so if you have a leak in your system it also will turn muddy quickly. Im sure its a good coolant but it has to be used in a completely sealed system where no outside air can get to it and must be mixed with distilled purified water plus a conditioner should be added periodically to mantain proper Ph levels to avoid corosion. I know for a fact that this stuff isnt good for plastic parts as we are seeing an increased number uf upper intakes fracturing between the EGR passage and coolant passages since they started using dexcool and on the older cars that still use the regular antifreeze there isnt nearly as much of a concearn with this. Ive found that on the 3.8 liter engine with the plastic intakes the customers that have opted to change to the green for thier 30k mile service have had cleaner cooling systems as well as having less problems with thier upper intake coming apart from the inside out. I for one will not use the stuff in my cars and will stick to changing the green stuff out every other year or so and so far none of my cars have had the problems that dexcoll cars have been having.

 

They adverise it as the 100,000 mile coolant, but if you maintain it like the green stuff, you'll get better aluminum protection than with the green stuff. And we all know aluminum radiators are a sizeable investment.

 

I've been using the Havoline Dex-Cool, it's silicate FREE, silicates are abraisave and bad for the water pump seal. I hear the red Toyota coolant is very good too. Here is an link to a HOTROD article about the Havoline coolant...Antifreeze Just Got Better

 

I have also heard very good things about the Toyota coolant from people that work at a Chevy/Toyota dealership.They say they will not use dex-cool but the Toyota stuff is great.I haven't tried it but I put faith in these guys and when I try it I'll let you know.

 

MY experience with Dex Cool has been excellent. I am the Vehicle Maintenance Manager at a ski resort in Park City Utah. Our fleet consists of 12 snowcats, 20 general vehicles (trucks, vans), and some miscellaneous heavy equipment. We run Dex cool in all of it. Of course all the Chevy trucks and vans come with it, and so does all the Caterpillar heavy equipment. But the Bombardier snowcats, Polaris snowmobiles and the few remaining Ford junk that we have, they have all been converted to Dex-cool at their first coolant change interval, thus ending all cooling system maintenance for the rest of the time we own the vehicle -except for a coolant filter on the snowcats once a year(down from 4 times a year, plus doing ph tests and managing additives...Ugh!). I was the first ski resort in the region to use dex-cool in cats, and now most of the other areas have followed suit. And they're loving it now too.

Besides the "no" maintenance advantages, we have observed some other characteristics: Better cooling, and LESS leakage. I'll explain. The snowcats are obviously designed to run in cold weather -at night, in the winter. Due to cramped quarters within the frame, and the supposed operating environment, the snowcats have radiators that are technically too small for the power they produce. Because of the cold temps, most of the time, they work great. But when pushing large amounts of snow on a warm spring day, it isn't uncommon for them to get hot, and the operator some times has to sit for a few minutes to let the cat cool. When we switched to Dex-cool, the over heat alarm notes on the oporators logs disappeared. That tells me that the Dex-cool has better heat transfer properties.

The other interesting observation we have made it that when there IS a leak such as a loose bleeder nipple, the stuff seems to coagulate and actually slow or stop the leak.

I also run it in my Trans Am, my Chevy truck, and and in my personal Polaris Storm 160 hp mod sled. All with no problems. No leaks. Just good heat transfer properties, and no maintenance. In this case, newer IS better.

 

This is what I was told about Dex-Cool by a GM engineer. Whether it's correct or not, I don't know...It's just what he told me. He said the Green stuff had a tendency to retain an electrostatic charge created by the spinning of the water pump. He said that the heater core, being the thinnest part of the cooling system, would go bad over time as a result of the small amounts of static electricity discharging to ground through the core..Supposedly, the dex-cool doesn't retain this electrostatic energy.... Again, just what i was told...I dunno how accurate this is..I DO know that I had to replace my heater core a while back with the green stuff!!

 

i work for toyota and we have a red color coolant that is bad a$$ if u have a leak it will actually "crust" up and stop small leaks.... hehe and it is good with plastic and all metals..... PLUS ITS FREE to me and me alone hehe so this is what i will be using.... its a great product..... just my .02

 

The Orange stuff should NOT be left in for 100,000 miles!!!

 

Might look at this from channel 4 TV:

http://www.nbc4.tv/automotive/2369813/detail.html