
Oil is the lifeblood of every engine and without it, functionality, protection and performance are impossible. High-quality oil flows through the engine ensuring moving parts move freely without grating against each other. The oil also seals parts against corrosive forces like rust, while collecting unwanted matter created by combustions and filtering it to the sump where it can’t cause harm. Finally, engine oil helps cool the engine, preventing it from overheating.
Without enough oil, components grind up against each other and cause damage, generating excessive heat. Engine performance is also negatively impacted, leading to poor fuel economy and higher running costs. Without the protection of oil, engine systems become clogged with debris and metal parts become susceptible to rust, which can make them brittle and breakable and make vehicles unsafe to use.
As a result, this makes running out of engine oil an eventuality best avoided. Purchasing a supply of engine oil only to find it has deteriorated and has become inferior or unusable over time is a waste of money, so it’s important to answer the question, “Does engine oil have a shelf life?” before bulk buying.
Understanding the shelf life of engine oil
In simple terms, the shelf life of standard motor engine oil is typically up to five years. These built-for-purpose oils are not a product that will go bad in a matter of months. However, it’s next to impossible to accurately predict just how long engine oil shelf life is. The reason for this is that petroleum stability, which refers to how effectively it can resist change to its unique properties, depends on specific circumstances. Mainly, this involves how much exposure oil incurs to factors that can speed degradation.
Petroleum-based products deteriorate due to chemical reactions that begin every time that they are exposed to like air, light, water, and oxygen. As a result, how well you store engine oil has a powerful influence on the product’s shelf life. Accounting for such considerations, exposure can reduce the lifespan of the engine oil from five years to two years. As a rule, storing engine oil where it won’t face exposure to high heats for extended periods and ensuring it’s correctly sealed so it’s not exposed constantly to air or is at risk of developing condensation will see its shelf life extend considerably.
Assessing the usability of engine oil
If you are unsure how old engine oil in your garage is, a visual examination will update your understanding. Pour some oil from the container into a vessel so you can study it. Fresh engine oil is usually pale brown in colour. If the engine oil is substantially darkened, it has likely oxidised. However, if the oil is milky in appearance, it has probably been contaminated by water. Look for signs of settling, a hazy appearance or for signs of particulates present. If your examination uncovers any of these issues, the engine oil is not fit for use.
How long can engine oil last in a vehicle?
Another question that often concerns drivers and vehicle operators is just how long engine oil can last in their car, truck, or van. The longevity of oil in cars depends on particular circumstances, but concerns driving conditions rather than storage practices.
Driving conditions are considered the key determiner when it comes to the active service lifespan of onboard engine oil. The reason for this is that how long an engine oil lasts is directly connected to how swiftly its additives are depleted. In its most basic form, an engine oil is composed of a base oil and an additive package. The base oil is virtually unlimited in terms of lifespan compared to the additives it contains designed to enhance and protect the engine and its operation. These detergents, acid neutralisers, and dispersants get consumed as vehicles are driven and they perform their role inside the engine.
After its additives become depleted, the engine oil can no longer provide proper protection for the engine, making an oil change absolutely necessary. There are two ways to check when it’s time to change your vehicle’s engine oil. The first is to consult your vehicle handbook where your automaker will have listed the ideal oil change interval for your make and model. Under normal driving conditions this is typically around every 7,000 miles but when vehicles are used in severe driving conditions, this drops to every 5,000 miles. The alternative option is to do a visual test of the oil in your vehicle by taking a sample and examining it as described above.
Finally, avoid overbuying oil you won’t get through and store it safely and correctly. Keep your supply well organised and dated to ensure you use older engine oil first and avoid waste.