dexcool vs. old green antifreeze
 

i recently was informed that mixing orange dexcool antifreeze and green antifreeze will cause harmful acid to form, which in turn would make the color brown and eat away at all your metal. i thought they could be mixed? what if you flushed your system out and got most of the green out, and put in dexcool?

Correct, but backwards. GET RID OF THE DEXCOOL. The orange stuff eats head gaskets, and aluminum parts for breakfast. If your warranty is expired, flush the system, full her up with good ole green stuff. Don't mix the 2, but get rid of the Dexcool!

jester is correct never mix the two!! or do a change over from green to dexcool unless it's a rebuild engine with all new hoses, rad boiled out, and possoible hearter core, the dexcool sticks to the parts and will transfer to the green making it sh it.

dexcool is not cool.

Seems like there was some kind of recall on the stuff in certain cars.

well here is my situation. 1 1/2 years ago, i had a shop install a new water pump and radiator, they flushed out the system and overflow tank(how well i dont know), and used dexcool. it's still orange, not brownish, so i think most if not all of the green stuff was flushed out. i had no idea that dexcool was so bad, my mechanic never said anything negative bout it, he acutally recommended it, i have not been going to him for some time now anyway. now, what do i do?

1) flush out all dexcool and replace with green?

2) keep using dexcool?
i was told this is the better solution since mixing the 2 causes acid formation, flushing out dexcool and using green again will cause more acid to form since there will be some dexcool left in the system.

Get rid of it. Flush out the system as best you can, and put the green back in. Mixing a miniscule amount of residual dexcool with new fresh green stuff pales in comparison to the damage you're gonna have if you leave straight dexcool in there.

There WAS a recall, well more specifically a TSB (Technical Service Bulletin) on GM's running dexcool. I've changed COUNTLESS GM heads, head gaskets, water pumps, heater cores, and radiators. While a surprisingly small amount of the same years models of Ford's and Mopar's. What did they have in common? You guessed it. I've actually seen dexcool settle out of water in a puddle in our parking lot. Looked like oil and water.

Just my $.02!!!

I must be lucky. I put dexcool in my 89 4yrs ago with no problems as of yet. My 96 blazer has always had dexcool. But I did have to change out the lower intake gasket once. I better switch back to the green stuff.

been doing a little research. i switched to texaco havoline when i replaced my radiator, water pump, and flushed system. 1 1/2 years later, its not discolored, and no problems. a good friend of mine has been running it on his high performance boat and all his cars for 5+ years w/o problems.

i was reading up and found that texaco havoline uses a different set of ingredients/formula which out performs shell decool,GM decool, and so on. no this was not info from texaco's website. all those GM's with cooling problems are running GM dexcool, which is sh*t

reqular green antifreeze leaves hot spots, which the havoline sort of coats those areas to trasfer and release heat, eliminating hot spots. havoline also works really well on mixed metals, which is what the 5.0 is made of. havoline also has the same ingredients used in Water Wetter by Redline.

I think when I flush it all out, if its still bright orange in color and there is no scale/sludge/corroosion in the old antifreeze, i'll refill with havoline. my water temp is a constant 195*, no matter what, it must be working. and if there are no signs of corrosion so why change it?

well, there's my sales pitch. i could be wrong

I hate dexcool, sucks, and yes it will eat away the head gaskets. You don't hear much about it and there is a reason... The car came with green stuff, use green stuff.