Offroad-Express

Just thought I'd post what have just happened to my navara, and if any one has an answer.
It a 2005 navara d22 zd30, over heated on way to work when we looked at fluids oil seams normal but there is oil in radiator, gave it a head check and head seam to be fine. Any one have idea why there is oil in water?

probably hole in the oil cooler. unless there is a crack between oil gallery and water jacket.
edit: just thinking that if it overheated its probably done the head. might have warped the head enough to get oil past the head gasket.