Oil leak into radiator seems that it has been doing this for at least two years on my 2002 Montero Sport by Mitzsubishi
better check for head gasket leaks, your oil look bad?
I had the same problem. It was not the head gasket but the radiator. Oil flows to the bottom of the radiator where it is cooled. There are 2 small tubes that connect to the bottom of it. This is where the oil flows. You will need to change out the radiator, hopefully this will cure your problem.
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