1. 殘留油污: After draining the old oil from the engine, some residual oil may remain in the oil pan, filter, and other components of the oil system. This residual oil can mix with the new oil, causing it to appear darker.
2. 未完全混合: If the new oil was not thoroughly mixed with the residual oil, it may appear black due to the uneven distribution of the new oil.
3. Engine Break-In: During the initial break-in period of a new or rebuilt engine, the engine components may shed metal shavings and other particles that can darken the oil.
4. Oil Type: Some types of engine oil, particularly those formulated for high-performance engines, may have a darker color even when new.
5. Short Oil Change Intervals: If you change the oil more frequently than recommended, the oil may not have time to accumulate significant contaminants and may still appear black.
6. Oil Filter Quality: A poor-quality oil filter may not effectively remove impurities from the oil, causing the oil to appear black sooner.
7. Engine Condition: If the engine has internal issues such as excessive wear or deposits, these contaminants can darken the oil.
If the oil appears excessively dark or dirty after a short period of use, it is advisable to have the oil and vehicle inspected by a qualified mechanic to identify and address any underlying issues.
