What Does Oil Life and Oil Life Remaining Mean?

by Synthetic Oil | Last Updated: July 1, 2022

You know that oil is important for the life of your vehicle’s engine. Without it, your car won’t run properly. To assist with keeping your vehicle’s oil in good condition, manufacturers came up with the Remaining Oil Life Indicator. But what exactly does “oil life” mean, anyway? Today, you are going to learn why it is important, what it means, and how to use the oil life remaining light on your dashboard to your advantage. Let’s get started.

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What Does Oil Life Mean?

Another way to say “oil life” is to say “oil lifespan.” The lifespan of your car’s motor oil is going to vary by brand, type, and use. If you want to estimate how long oil will last in your car, you should look at the label on the oil container.

Here is a look at the different kinds of motor oils available and their estimated oil life:

Conventional Mineral Oil

One of the most available and affordable options, conventional mineral oil typically has a life of 4,000 miles. Many older model cars continue to use conventional oil, though most manufacturers in present times have been recommending full synthetic for their vehicles.

Semi-Synthetic or Synthetic Blend Oil

A mixture of conventional and synthetic oil, this one has an oil life that is longer than conventional but shorter than full synthetic. Many truck and SUV drivers choose synthetic blends. Lifespan varies based on the brand, type, and ratio of the blend. That said, most synthetic blends last between 7,000 and 10,000 miles.

Full Synthetic Oil

Used in all kinds of cars, including high-performance vehicles. Synthetic oil can last between 10,000 and 25,000 miles, though that will depend on the brand and several other factors.

High Mileage Oil

Created for vehicles with over 75,000 miles, the lifespan is based on the brand and formula. You will have to check the labels on the containers for more information.

Oil Life Remaining System Development

Also known as an oil change reminder, the Remaining Oil Life indicator on your dashboard is part of a system that keeps tabs on how long a batch of motor oil has been in use. The system was designed to track the amount of mileage and time the engine has been used since the previous oil change. The big picture is that knowing how much time your oil has before it no longer adequately protects the engine is a huge bonus. However, the system is not always easy to understand. Nor is it entirely foolproof.

The first thing you need to know is that there are no sensors involved in calculating the remaining oil life—at least with older models. Once upon a time, the “3,000-mile oil change” was the rule of thumb that everyone went by. But that was when conventional oil was most popular and synthetic oils with additives, detergents, and other chemicals were not a thing. Oil life remaining systems are more of an educated guess.

Modern Day Oil Life Monitors

Newer vehicles have built-in intelligent oil life systems, such as Ford. Basically, the system is based on the data collected by vehicle manufacturers. Other data includes the suggested type of oil and vehicle performance under various conditions. The monitor also keeps track of cold stars, drive temperatures, idling hours, driving hours at a constant speed, and the number of engine revs. Then that information is used to give the remaining oil life system an idea of when your oil is going to run out.

Whenever you change your oil, the oil life indicator resets to 100% (some vehicles must have this done manually). When the light flicks on, it means that 30% oil life remains and that you will need to change your oil soon. This calculation is assisted by the odometer.

Factors Affecting Oil Life Percentage

The main functions of your oil is to reduce friction and protect the engine from harm. Unfortunately, the longer you go without changing it, the worse the oil gets at doing its job. There are also some circumstances that accelerate the degradation of the oil. Let’s have a look at some of the factors that affect oil life—and how fast your oil life indicator turns on.

Heat

This does not refer to the outside temperature but the operating temperature of your vehicle. The higher the operating temperature, the greater the need for fully synthetic motor oil. For example, if your truck has been hauling a heavy load all day long, the engine is going to get warmer than average. Cars that have been modified with superchargers, too, tend to run at higher temperatures.

Heat is the enemy of motor oil, which seems counterproductive, but it’s true. Heat breaks motor oil down more quickly, leaving deposits of sludge around the intake valves. When that happens, the airflow through the engine is hindered, dampening performance. Moreover, since the combustion chamber is not getting enough air, there could be misfiring and diminished fuel economy.

Distance Traveled

The lifespan of oil is listed in the number of miles you can typically travel before the oil gets dirty and needs to be changed. Some brands of oil may only permit 5,000 miles, while others will guarantee at least 10,000 miles.

Therefore, if you find yourself commuting a lot, you may need to choose an oil formulated to suit your vehicle usage.

Environmental Factors

Another reason oil life is decreased is from environmental factors. For instance, if you have just taken a road trip in your pickup truck through the Mojave Desert, you probably picked up loads of dirt and dust. Sometimes dust and dirt will get into the engine, where it mixes with the oil. Dust and dirt particles are too small to be captured by the oil filter, so those contaminants continue to cycle through the oil.

Aside from dirtying the oil and making it less effective at cleaning away grime, dirt and dust also affect the oil’s suspension and flow. Should there be too much dirt in the oil, the slower the oil flows through the filter and back into the engine.

Dirt stresses the additives and detergents. It makes operation laborious, and that will begin to affect the overall performance of your vehicle. As such, if you are consistently driving through dry climates or windy areas, the oil life remaining indicator is going to turn on sooner than if you were driving through rain all the time.

Age of the Vehicle

Aside from technological advancements, older cars are just simply less efficient at utilizing oil. This is because they tend to run at higher temperatures than newer models. Additionally, the wear and tear found in older engines make them vulnerable to leaks and other issues that eat through oil.

Check Manufacturer Recommendations

As mentioned earlier, the lifespan of oil is truly hard to pin down. While you could live by the belief that every 3,000 miles to 3,500 miles is ideal, there are some synthetic oils that can protect your engine for 20,000 miles or more. That is why you should look at the manufacturer’s recommendations in the vehicle’s owner manual. In the manual are guidelines that tell you the best kind of oil to use, when to change it, and when you should also swap in a brand new oil filter.

The manufacturer will also give you some ranges for normal and severe service intervals for your next oil change. Normal service intervals include your routine commute at a steady speed. Stop-and-go traffic is a little harder on the engine. Towing a heavy load or racing around a track is considered severe.

Using the manufacturer’s guidelines, you should be able to develop a decent timeline for the length of the oil’s life, as well as when you will need to change the oil. However, it is always best to err on the side of caution and refresh your vehicle’s oil sooner than later.

Examples of Oil Life Recommendations by Manufacturer

Here are some numbers from popular automobile makers:

• Jaguar – 15,000 miles
• BMW – 15,000 miles
• Infiniti – 7,000 to 10,000 miles
• Ford – 7,500 miles
• Honda – 5,000 to 7,500 miles (based on the manual from a 2016 Honda Civic)
• Hyundai – 5,000 miles
• Kia – 5,000 miles
• Toyota – 5,000 to 10,000 miles, depending on the oil type.
• Nissan – every 3,000 to 5,000 miles for conventional, or 7,500-10,000 miles for synthetic
• Chevrolet/GM – 7,000 to 10,000 miles

Do keep in mind that these numbers are for newer models, primarily models made around 2010 and later. Any vehicle prior to that will be considered an older model and should follow the 3,000 to 5,000-mile rule. Again, it is best to check the owner manual for the recommendations from the manufacturer first.

Conclusion

So what does oil life mean? It means the number of miles a car can travel before the oil in the engine needs to be replaced. When your car is nearing 30% on oil, the remaining oil life indicator may pop on to remind you to change it soon. Older cars may not have the same technology as newer models, though, so you should listen to the manufacturer’s recommendations, even if the oil life remaining light does not turn on. But if it does come on, do not ignore it!