Hi guys, i have a question concerning the O2 Sensor. It says in my repair manual to replace the o2 sensor every 60,000 miles. Why is this? Im looking at my repair manual right now at the CHECK ENGINE BLINK CODES and there is one code and two Diagnosis pertaining to the o2 sensor: The first Diagnosis is (Detection of O2 sensor Deterioration), the second one is (Problem with O2 sensor Heat signal). This leads me to my next question, If the reason why i have to replace the sensor every 60,000 miles is because of failure or deterioration then why not let the computer pick up on it with a check engine light rather then replacing a potentially good o2 sensor that can be used for thousands more miles. I think its a wast of money and a gimmick to get you back in to the dealer for replacing. Correct me if im wrong.