This is almost certainly due to a blown head gasket, which will have to be replaced. Oil and water systems will need to be flushed and refilled with clean oil and coolant
Could be a head gasket but it could also be from corrosion holes behind the water pump impeller if it is a diesel with an oil cooler , the oil cooler core has a habit of fracturing on nissan diesels
Answers & Comments
This is almost certainly due to a blown head gasket, which will have to be replaced. Oil and water systems will need to be flushed and refilled with clean oil and coolant
Could be a head gasket but it could also be from corrosion holes behind the water pump impeller
if it is a diesel with an oil cooler , the oil cooler core has a habit of fracturing on nissan diesels