1996 sunfire w/2.4 has oil in radiator reservoir

[mopar440cu]

Does anybody know if having oil in the coolant reservoir a sign of a bad head gasket, a leaking manifold gasket or the transmission cooler leak in the radiator? The car has zero water in the engine it self and has no white smoke out the tail pipe with no loss of power. I checked the auto tranny and no oil mixing with water there either? Im lost on this one

I did search on here for other people with the same issue but came up with nothing.

 

[melsg5]

sounds like the trani cooler. The pressure in the trani cooler lines is higher than the water pressure. Do a hydrocarbon test on the coolant to rule out the head gasket.

 

[mopar440cu]

sounds like the trani cooler. The pressure in the trani cooler lines is higher than the water pressure. Do a hydrocarbon test on the coolant to rule out the head gasket.

Thanks but, I have to some how clear out the oil in the radiator and reservoir. I don't know if it is in the block, I'm guessing there is. I have the radiator out now trying to figure out how to flush it out.
Thinking about it, wouldn't motor oil in the radiator be brownish color, while ATF be a pinkish color though? This color is brownish.

 

[melsg5]

any petroleum based fluid when mixed with antifreeze produces a brownish material