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
Chevrolet G Series Van (G20) Intake Manifold Gaskets May Leak Coolant or Engine Oil
Chevrolet G Series Van (G20) Problem
Engines Affected: 5.7L V8, Gasoline
Average Mileage: 138,620 mi (107,000 mi - 178,643 mi)
replaced water pump and thermostat notices coolant leaking for the under the middle of van underneath engine when i turned off van . also the temp teeter totters between hot and cold
Visitor, 1994 Chevrolet G Series Van (G20), 5.7L V8, 178,643 mi
Noticed moisture on the top of the block when doing a tune up and seepage from the water pump. The water pump itself has been giving off a bit of extra noise then I'd like to deal with and with winter just around the corner, I don't want to get caught out in the rain dealing with any of it. This is typical of these motors. So I Replaced both intake gaskets, heater hoses (they were shot) and water pump. No more noise or seepage problems. A good Saturday afternoon's work.
Visitor, 1994 Chevrolet G Series Van (G20), 5.7L V8, 107,000 mi
Saw coolant leaking from front of manifold.
removed manifold, found more leaks between head gaskets into oil.
replaced with new gaskets, problem solved.
Visitor, 1994 Chevrolet G Series Van (G20), 5.7L V8
I have gotten a leak from the radiator and the intake gasket (outside) Radiator repaired and hoses . Did not bother with the small leak of the intake manifold
Visitor, 1993 Chevrolet G Series Van (G20), 5.7L V8, 113,000 mi
breather grommet went first. easy fix.then intake gasket along with manifold gaskets...though manifold may have crack in it...wont know until it is pulled. hear these vans have manifold cracking issues (darnit. Already replaced transmission at 112k. Also, rear diff seals shot and have to replaced. Happy Trails.
Visitor, 1990 Chevrolet G Series Van (G20), 5.7L V8, 150,459 mi
really its 1988 but yeah im thinkin about do all gaskets since coolant n oil is mixed SMH