The need for an oil change every 3 months for a car is usually closely related to the usage environment, oil type, and driving habits. In such cases, changing the oil quarterly can protect the engine. For turbocharged models or commercial vehicles (such as taxis), although fully synthetic oil is labeled for replacement every 1 year or 10,000 kilometres, the interval should be shortened to 3-5 months under high-intensity use, particularly when the monthly mileage exceeds 3,000 kilometres. Additionally, if the vehicle undergoes a break-in period, experiences engine overheating, or remains parked for extended periods, oil oxidation and metal debris accumulation will also necessitate earlier oil changes. It is best to test the oil by placing a drop from the dipstick onto filter paper: if only a dark deposit ring remains or no diffusion ring is present, the oil should be changed immediately. Following the "whichever comes first" principle (triggered by either time or mileage) and replacing the oil filter simultaneously can prevent engine wear caused by oil degradation and ensure the vehicle's long-term performance stability.
