How often should the engine oil be changed for a car that is not driven frequently?
3 Answers
If a car is not driven frequently, the engine oil should generally be changed every six months. Here is a detailed introduction to the functions of changing engine oil: Cleaning performance: Engine oil can clean and disperse these by-products, preventing them from coagulating inside the engine and keeping it clean. Protective performance: Changing the oil flushes away dust, impurities, water, and other substances, protecting the engine and ensuring its normal operation. Lubrication performance: Engine oil has a shelf life. Timely oil and filter changes help clean and filter various impurities, preventing them from causing wear and tear to the engine.
Having driven for over a decade, I've learned that leaving a car idle for long periods definitely requires attention to oil issues. Even with minimal mileage, engine oil can absorb moisture and oxidize over time, potentially causing internal engine rust or sludge buildup. Most manufacturer manuals specify changing the oil at least every 12 months regardless of mileage. During the pandemic when my car sat unused for months, I delayed the oil change and later noticed strange engine noises upon startup - inspection revealed the oil was full of contaminants. Fortunately, no major components were damaged. Now I set annual calendar reminders for oil changes while also checking battery and tire conditions. When vehicles sit too long, oil degrades rapidly. A simple oil change costs just around a hundred bucks, far cheaper than major engine repairs and the accompanying hassle. Regular maintenance means peace of mind and better resale value.
I'm a daily driver who doesn't often go on long trips, and the car is usually parked in the garage. A friend suggested checking the engine oil every six months, but since I don't drive much, I think changing it once a year is practical enough. Oil aging is mainly due to oxidation and moisture absorption—if the car sits idle, the oil deteriorates, and its lubricating effect diminishes. The last time I checked my oil, it had darkened after six months of inactivity, indicating it had started to degrade. Before changing the oil, I usually start the engine to listen for unusual noises or open the oil cap to check for a sour smell. The cost isn't high, and changing it once a year isn't much of a burden while preventing increased engine wear. Otherwise, a seized engine would be a much bigger problem. I often ask mechanics for advice, and they all say not to delay oil changes too long for the car's health.
