How often should engine oil be changed if the car is not used for a long time?
3 Answers
If the car has been parked for as long as half a year, it is best to change the engine oil immediately before driving to ensure the engine operates in the best condition. When a vehicle is parked for an extended period, the engine oil can deteriorate due to oxidation, leading to reduced performance. It is crucial not to continue using degraded oil to save money. Additional Information: 1. First, it's important to know that engine oil is categorized into mineral oil and synthetic oil. Synthetic oil is further divided into full synthetic oil and semi-synthetic oil. The shelf life of mineral oil is 3 months, semi-synthetic oil is 6 months, and full synthetic oil can last up to 1 year. 2. Even full synthetic oil with a shelf life of 1 year will experience performance degradation after half a year. 3. Therefore, in daily car usage, apart from considering the mileage to determine if the oil needs to be changed, the duration of oil use should also be noted. For specific models, refer to the vehicle's maintenance manual for the exact mileage and duration, and follow the mileage and time specified in the manual.
I don't drive my car much, and it often sits idle for half a year at a time. Don't think you can skip oil changes just because the car isn't being used. Even when stationary, engine oil will gradually oxidize and deteriorate over time, causing the oil film to break down. Generally, it's recommended to change the oil at least once a year. If the car is parked in a humid environment or experiences large temperature fluctuations, changing it every eight months is better. If the car sits unused for a long time, always check the oil condition before starting it—look for signs of emulsification or a milky appearance. Last time, my car sat for nine months without moving, and the oil had even separated into layers, so I had to change it immediately. Also, remember to check other fluids and the battery. A car that sits unused for too long can develop many issues, so regular maintenance is still necessary.
I used to have the misconception that if a car is left unused, the engine oil doesn't need to be changed. Later, I specifically consulted an experienced mechanic and learned that over time, engine oil absorbs moisture and forms acidic substances that can corrode engine components. Even though full synthetic oil has a longer lifespan, it must be replaced if the car has been parked for over a year. Now, I change the engine oil roughly every ten months, while also checking tire pressure and brake discs. Before driving, I always let the car idle for five minutes to allow the oil to circulate. By the way, it's best to replace the oil filter during an oil change to prevent impurities from clogging the system.
