Originally Posted by mjr46

well ,the way a gm rep explained it to me in a class I had a long time ago, not sure if it's true or not but the compound make up of dexcool reacts with the metals and gasket material and deteriorates it over time when dexcool is exposed to the atmosphere, via leaks.......it also sludges if not serviced at proper intervals, the 3.1 and 3.4 intake gaskets were of plastic and rubber construction and over a period of time and numerous heat cycles coupled with the dexcool reacting with the materials they deteriorate and spring leaks in the corners, the worst one I did was a malibu last year, when I removed the intake the leaks had sprung internally and had plugged up the oil drain back holes in the heads and filled the intake with globs of soft pasty sludge due to mixing with oil, we used a special air powered suction gun and funneled the crap into a paper bag, what a mess!!!