One post mentioned that DEX-COOL corroded Aluminum. Actually it doesn't it seems to have a bad reaction when in contact with certain plastics. From 1996-2003 the LIM Gaskets were constructed of a Nylon material called Nylon 66. Over time DEX-COOL and this Nylon gasket were in conflict and the gasket lost. In 2004 GM changed the gaskets to an Aluminum one but only in their Flag ship vehicles like the 3.8's in GP, Monte Carlo, Impala. If ya have anything older than a 04 I would consider dumping DEX-COOL 04's and up I would change the DEX-COOL yearly every two for sure. It's not cut in stone that the new gasket won't fail but it suppose to have a better chance.
