The intake manifold gasket may develop and external engine oil or coolant leak. In some cases, an internal coolant leak may occur causing coolant to mix with the engine oil. Running the engine with a coolant/oil mix may result in engine damage. Replacing the intake manifold gasket should correct this issue.Google+
Car Problem Reports
GMC Savana 1500 Intake Manifold Gaskets May Leak Coolant or Engine Oil
GMC Savana 1500 Problem
Engine Affected: 5.7L V8
Visitor, 1999 GMC Savana 1500, 5.7L V8, 74,000 mi
Leaking at left rear corner. This thing has been babied, and I have continuous problems. Shocks, springs, water pump, transmission solenoids, etc. etc. I have always bought American cars but I'm about done.