Custum73

Was getting ready to flush my cooling system and a friend recommended changing to the Prestone extended life coolant. Then a gentleman posted a reply on another forum recommending NOT to switch to DEXCOOL. Which do you use/recommend?

markdtn

I swapped my truck when I changed radiators and water pumps (and hoses). A year later the orange stuff ate my water pump gasket. My opinion-if it came with orange stay orange, if it came with green stay green.

Steve Straus

I agree. The dexcool ate a radiator and a water pump in my sister's blazer. There's some kind of reaction it has with certain metal compositions, but I don't remember the details. I ran it in my Vette and had a corroded expansion tank and left side radiator tank about a year later. These were new parts mind you. I just don't see the extended life of the coolan outweighing the shortened life of the cooling system. If the system was designed for it, that's another thing entirely. I'd stick with the green stuff. If it can cool my big block, it can cool anything.

vettfixr

I switched over to Dexcool a few years ago. Up to that time I changed the coolant yearly even though my car gets fewer than 2K miles per year. Each time I drained the system there was an abundance of rust and corrosion. After changing to Dexcool I no longer get the rust and corrosion and I haven't had any problem with cooling or destruction of other parts. I'm going to stick with Dexcool.

norvalwilhelm

My new motor and aluminum rad started life with normal green anti freeze. After a year the inside of my new aluminum rad was all cruded up. I made the switch to dexcool and the rad cleaned up internally like new.
I have used it in the vet for years and everything inside looks new.

zwede

The vette has been on a Dex-Cool diet for the last 4 years. Replaced it last year and it was still clear with no corrosion. I'm sticking with it.

Custum73

Well, you guys are 50/50 so far. At first, I was scared back into going with the green stuff, but then some guys mentioned how the dexcool cleaned up their systems. So I'm torn so far. I sure as hell don't want to have to replace parts, so it sounds like green is the way to go, but if the dexcool cleans up the rust, should I go with that? Sounds like the safe bet might be to just go green and flush annually.

jrzvette

If you try this change you have to make sure that you get ALL of the green stuff out of your cooling system. The green and orange are not compatable and you will end up with a sludge that will clog everything.

Custum73

I definitely plan on flushing the system a number of times, before and after using the Prestone super flush.

Ronny

You're on the right track Custom73, flushing with a chemical flush and then clear water. There is a new Zerex anti-freeze on the market know as Geo-5 it is yellow and you will see it in new Ford's especially trucks and it is compatiable with all other types. The recycler that does my waste anti-freeze speaks highly of it. I have priced it and it is same as Dexcool. Understand that GM is involved in several large class action lawsuits over Dexcool, which has problems of unknow origin. It will not go 100+ thousand miles without maintenance as claimed. Best of Luck

rosslato

aluminum radiators and dexcool go hand in hand. dewitt aluminum radiators recomends dexcool in their radiators.

MN-Brent

Dexcool if not properly maintained with gum up your system. Look for heater core pluggage and radiator internals coated for reduced flow efficiency. It leaves a brown peanut butter coating that is impossible to remove. You must replace the radiator and heater core if you are unfortunate.

There is also a problem with certain style OEM radiator caps used with Dex-cool. There is a recomendation to replace some with a center style pressure release caps, might even be a GM service bulletin on this.

In my 1998 ZR2 blazer, I replaced old with new Dex-Cool at 60K and saw only a slight build-up so far.

Brent...