Thanx for that link, Terry... Good info....

I've personally seen the Dex-Cool turn to jello when mixed with regular, green coolants...not a purdy sight at all....

When I put in my Dewitts aluminum radiator, I called Dewitt and asked him what he recommended for his radiator.  He said it didn't really matter but stressed that I mix it with distilled water only.

[QUOTE=F4Gary]When I put in my Dewitts aluminum radiator, I called Dewitt and asked him what he recommended for his radiator.  He said it didn't really matter but stressed that I mix it with distilled water only. [/QUOTE] That is the real choice in my book..........distilled water. There aren't any minerals in it. Or if you can use reverse osmosis water. Of course mixed with the anti-freeze.

I can tell you from personal experience on a '96 GMC Truck that Dex-Cool SUX.  71Shark and I had to drill and tap a heater hose neck 'cause the Dex rotted out the aluminum quick release fitting. 

There is a class-action lawsuit against GM for the damage dex-Cool has caused.  There was mud in my system and when we changed the head gaskets, even though we had flushed and refilled with Prestone Green, the head gaskets were eaten alive. 

Also, don't fall for the Prestone trick out there that proves P.T. Barnum was right.  The 50/50 Prestone costs more per gallon in some stores, and only a buck or two cheaper that the full strength stuff.  Paying for convenience is one thing, but that is crazy.

I would recommend that after you flush several times (don't forget to flush the heater core as well, do a BLOCK FILL of the system, SLOWLY, watching for bubbles.

One of the corrosion issues with Dex-Cool is that when it goes away, the airspace corrodes, so the lower the system, the more corrosion.

GM is about to find out how much they will lose (up to $800/customer) for damages due to Dex-Cool. <url>http://www.consumeraffairs.com/news04/2008/06/dexcool_settle.html<url> 

I was told by the local manager of Auto Zone that Dex-Cool is no longer being prduced and is being sold to empty the stocks.

As our local vette mechanic loves to say, "New does not mean works", usually meant to mena parts, but applies well here.