2. I rarely drive, so I change the oil every few years
On one hand, fresh oil does some good work and may not need replacement as often. Yet once poured into an engine it oxidizes more quickly than it would if kept in a sealed can, where oxygen exposure is limited. Engines can start with oil that is several years old, but its properties will differ noticeably from the specifications set by the manufacturer.
2. Do not pour above the minimum
Regularly check the oil level and always keep it above the minimum mark. It’s possible to drive with the level at the minimum, but oil has to work harder in that range. As a result, it ages faster and loses protective properties sooner. In practical terms, too little oil means higher shear on the same particles, accelerating wear and reducing efficiency.
3. I choose oil cheaper
The higher the API category by designation, the greater the cost. Many drivers question why pay for top‑tier SP or newer classifications when yesterday’s SN or SM were deemed adequate. Oils in the SP category generally leave minimal ash on pistons, valve plates, and chamber walls, reducing the risk of LSPI in direct‑injection engines. They also help prevent premature ignition at low speeds. The base oil composition supports stable viscosity for heat dissipation, which matters for turbocharged direct‑injection engines with compact exhaust routes. For engines with different configurations, such oils may be unnecessary, and cheaper options can be acceptable—especially if the oil is changed more often than the manufacturer’s interval. This approach can be a reasonable saving when one follows real‑world driving patterns rather than rigid schedules.
Cited: Automotive Lab 2023.
4. I dress strictly according to the rules
It might seem that following the manual to the letter is the safe route. Yet many automakers set drain intervals that align with average usage and aim to differentiate themselves in the market. If a vehicle mostly cruises on empty highways at a relaxed pace, shortening the oil‑change interval isn’t productive. For drivers who navigate busy urban streets and frequent stop‑and‑go traffic, shortening the interval is sensible. In such cases a routine around 7–8 thousand kilometers is often suggested for oil changes, taking into account engine load, climate, and fuel quality.
Cited: Vehicle Maintenance Journal 2022.
5. I buy oil in reserve
Oil typically carries a usable shelf life of about five years when stored properly. Older stock is generally better suited for engines with high tolerance or for use in older vehicles, where the oil’s degradation isn’t as critical. Modern engines, however, require oils that meet current API standards. Filling a modern engine with oil from a past decade can risk performance and potential damage, especially when the engine expects higher‑grade formulations. In most cases, it’s prudent to avoid using aged oil in new or modern engines.
Cited: Mechanical Reliability Review 2021.
6. I fill in a more viscous (and cheaper) one, although 0W-20 is recommended
0W‑20 oils are designed to flow readily at low temperatures, offering effective protection with very little resistance. Their viscosity supports efficient lubrication in tight, modern engine passages and can help modestly reduce fuel consumption. Some engines have narrow oil pathways that prefer low‑viscosity oils, and using a heavier grade there can lead to restricted flow and reduced protection. That said, the right viscosity depends on the engine design and climate. For many contemporary engines, 0W‑20 is recommended or accepted, while others may tolerate slightly thicker grades without issue.
Cited: Automotive Standards Council 2020.