Problem Description and Possible Solution
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.
Average mileage: 155,062 (100,000–206,000)
Engines affected: 4.3L V6, 5.0L V8, 5.7L V8, Gasoline
30 people reported this problem
This was the second set! The first set was replaced at 60,000 miles with the same, problematic AC Delco gaskets. The second setrecently installed are the "improved" Fel-Pro brand gaskets. It is not a matter of "if" the gaslet is going to fail, but "when" is the gaslet going to fail.
Very common on this vehicles, generally you will notice a coolant leak near the front of the intake manifold, above the timing chain cover.