Oil in the anti freeze
smackey54
02-22-2010, 07:16 AM
2003 Grand Am Gt found oil in the Anti freeze & engine oil low no external leak on engine has any one seen this and what should I do next?
GTP Dad
02-22-2010, 07:51 PM
Welcome to AF!!
Are you sure this is oil and not Dexcool residue. The oil can burn off and not actually leak out. Dexcool has a history of producing an oily residue in the overflow tank and it is sometimes confused with engine oil.
If it is truly engine oil it could be a bad intake manifold gasket although you didn't say what size engine you have in your car. If it is a V-6 the intake manifold gasket is a possibility but usually this results in water in the oil not the other way around.
The other possibility is a faulty transmission oil cooler that is allowing trans oil into the cooling system. I would check the transmission for water as well. The higher pressure from the transmission will usually put oil in the coolant but when the engine is off the water can migrate into the transmission.
Are you sure this is oil and not Dexcool residue. The oil can burn off and not actually leak out. Dexcool has a history of producing an oily residue in the overflow tank and it is sometimes confused with engine oil.
If it is truly engine oil it could be a bad intake manifold gasket although you didn't say what size engine you have in your car. If it is a V-6 the intake manifold gasket is a possibility but usually this results in water in the oil not the other way around.
The other possibility is a faulty transmission oil cooler that is allowing trans oil into the cooling system. I would check the transmission for water as well. The higher pressure from the transmission will usually put oil in the coolant but when the engine is off the water can migrate into the transmission.
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