Engine oil deterioration diagnosis device

An engine oil deterioration diagnosis device for diagnosing engine oil deterioration in an engine of a vehicle, comprising:

• an annual traveling distance calculating part for calculating an annual traveling distance based on a traveling distance detected by a traveling distance detecting device;
• a used hour calculating part for calculating used hours per predetermined period of the vehicle based on used hours of the vehicle;
• a severe condition determining part for determining a severe condition when a relationship between the annual traveling distance and the used hours per predetermined period meets a determining criteria of the severe condition;
• an oil traveling distance calculating part for calculating an oil traveling distance based on the traveling distance;
• an oil traveling distance accumulating part for accumulating the oil traveling distance calculated by the oil traveling distance calculating part to calculate an accumulated oil traveling distance;
• and
• an engine oil deterioration diagnosis part for diagnosing that the engine oil is in a state of deterioration when the accumulated oil traveling distance calculated by the oil traveling distance accumulating part reached a predetermined value;
• wherein the oil traveling distance calculating part comprises:
• an oil traveling distance normal adding part for calculating the oil traveling distance by adopting the traveling distance, when the severe condition determining part does not determine the state as being in the severe condition;
• and
• an oil traveling distance addition correcting part for calculating the oil traveling distance by adding a predetermined value to the traveling distance, when the severe condition determining part determines the state as being in the severe condition.