Quote Originally Posted by bobc455 View Post
The Lower Intake Manifold gasket is frequently a problem, because people don't change out the antifreeze periodically like they are supposed to, and it turns acidic and eats the plastic gaskets. Replace with aluminum gaskets, and flush out the cooling system. You might also take this opportunity to convert to Ethylene Glycol antifreeze instead of Dexcool, but be sure your flush is thorough because the two don't play well together (unless you go to "universal").
Need to disagree with you Bob. If you replace with plastic frame gaskets, it does not matter what type of coolant you use the gaskets will begin to warp and implode. I tested this before metal gaskets were available. In as little as 20K, the gaskets were having issues.