Originally Posted by
Martin77
Usually following the service book is enough and yes technically one change is enough. You can also assess if a second drop and refill is required if the existing oil is dark brown and not red, smell (burnt), and current shifting is not smooth. If I were you I would buy 2 bottles (for 2 change) and if you don't need it, you can keep it for future change. Can you please tell me when the next change is due? Is it approx at 180k km? The oil should keep for a few years.
You should check if there is an inline filter used for the car. If so, it's good to replace it. I'm not sure about the presence of internal filter for your civic.