Yup, Dex-Cool is nasty stuff. Even for engines it was intended for, eats the gaskets. Lower intake leaks are common on GMs with Dex-Cool in them, especially the 3.8 V6.
This is true. I've had to replace the intake gasket on 3 different occasions. I had to replace it twice on the same engine before I learned my lesson. I avoid it.
Jon
