Engine oil is the lifeblood of your car. It lubricates internal engine components, keeps friction in check, and helps ensure smooth driving. But all these essential tasks take a toll as oil becomes contaminated over time and can no longer effectively perform its duty. At this point, it's time for an oil change. Thankfully, an oil change is reasonably priced and arguably the best bang-for-your-buck service you can buy.
But, an oil change brings up many questions. How often should it be changed? Does the schedule change based on the type of oil? And does the "every 3,000 miles" guideline still apply? Read on for the answers to these questions and more.
Background: Types of Engine Oil
Let's first be clear about the different engine oil types available today. Some may categorize things differently, but there are four engine oil types.
#1 Conventional Engine Oil
Standard motor (or engine) oil comes in various viscosities and quality ratings and has long served as the go-to lubrication choice for everyday vehicles.
#2 Synthetic Oil
While conventional oil is refined from natural crude, synthetic oil is chemically engineered and processed for specific lubrication functions. Mainly, this involves helping the oil to work more efficiently while offering more protective and anti-corrosive properties. Synthetic oil also performs better at high temperatures. So, it's well-suited for engines that operate at greater extremes and benefit from the specially formulated additives.
#3 Synthetic Blend Oil
Blends use a mixture of conventional base oil and synthetic additives to produce lubrication with particularly resistance capabilities or other qualities. Fundamentally, this is a traditional motor oil with hints of the protective benefits of a synthetic formulation.
#4 High-Mileage Oil
High-mileage oil is specially formulated for vehicles with over 75,000 miles of use. Special additives reduce problems like oil burn-off and leaks commonly occurring in well-used engines.
Oil Viscosity and Other Designations
The numbers, symbols, and badges on engine oil packaging can be overwhelming. Let's walk through the details, so you'll be ready when oil change time comes around.
Viscosity is the first consideration. If you live in a cold climate, you need "thinner" low-viscosity oil that flows more easily. Lower temperatures make it harder for thicker oils to move freely between the many parts of the engine. The Society of Automotive Engineers (SAE) created the ratings and informed us of all there is to know about viscosity.
Let's look at one example, SAE 15W-40. The number 15 before the W indicates the cold-temperature viscosity rating, and the 40 at the end is the high-temperature viscosity rating. Lower W numbers are better in winter because of better flow inside the engine.
Also, look for the API or ILSAC designation on the label; these show that the engine oil meets the minimum industry standard. It's not unlike seeing an FDA-approved label on a medicine packet. API stands for the American Petroleum Institute and ILSAC for the International Lubricant Standardization and Approval Committee. Look for these tags to help ensure you're getting a quality product.
How Often to Get an Oil Change: According to Mileage
Check the manufacturer-recommended maintenance schedule in the owner's manual if you're curious about the oil change interval for your car. The plan may be mileage- and/or time-based, and there may be recommendations for heavy-duty driving or operating the vehicle outside normal parameters.
Depending on the vehicle, an "oil" warning light on the dashboard may signal it's time for an oil change. But, an illuminated warning light could also mean there's just something wrong with the oil or the lubrication system.
The timing for an oil change varies depending on the car and when it was built. It's typical to see a 3,000-mile recommendation for 2010 or older vehicles, while newer autos frequently come with 5,000-7,500 oil change cycles. Much of this difference comes from newer vehicles using blends or synthetics which last longer.
There are other oil change cycles (1,000 miles and 10,000-15,000 miles) for extreme scenarios, which we'll cover later. Here's a breakdown of oil change mileage recommendations.
Every 3,000 Miles
Let's start with the common oil change recommendation of every 3,000 miles; it's a "magic number" often recited by mechanics and drilled into your head by "quick-lube" companies. This advice was 100 percent correct at one point, but things change as technology advances. Of course, if the owner's manual recommends every 3,000 miles, then stick with this schedule. And, there's no harm in changing the oil more frequently than what's suggested in the manual.
Every 5,000-7,500 Miles
Thanks to the wonders of modern chemical engineering (we're talking about blends and synthetics), an oil change every 5,000-7,500 miles is becoming the new normal. Much of this is dependent on the vehicle's age (usually ones built in the last dozen years), the type of engine oil, and driving habits. It all comes down to the manufacturer's recommendations and how rigorously a car gets driven.
Every 1,000 Miles
It may seem strange to suggest an oil change every 1,000-3,000 miles, but it makes perfect sense for a vehicle driven almost exclusively for short travels of 10 miles or fewer. Running errands and quick trips don't allow the engine to heat up enough to burn off condensation that builds up in the system. This excess moisture contributes to the faster breakdown of engine oil, as does the constant restarting of the powerplant or driving under extreme situations (such as heavy loads or a dusty environment).
Every 10,000-15,000 Miles
On the other end of the oil change scale is a 10,000-15,000 interval. It's a less common, but not impossible, recommendation that ties into the use of synthetic oil. But keep in mind that environmental conditions, weather, and driving habits can reduce this range.
How Often to Change Synthetic Oil
As we've covered, synthetic oil allows longer intervals between oil changes. But, there's a clear distinction between fully synthetic and blended synthetic oil. In general, a blend won't last as long because it's primarily conventional oil.
Why Does Synthetic Oil Last Longer?
Synthetic oil lasts longer because of the way it's made. Additional refining (beyond conventional oil) reduces engine friction and the production of oil filter-destroying sludge and contaminants. In short, the engine works better and is more protected.
This improved production allows for synthetic oil changes ranging from 7,500 miles at the low end to every 15,000 on the high side. In comparison, at best, a blended oil might last up to 6,000 miles.
Conclusion: Signs That You Need an Oil Change
Mileage is the most common determinant of the need for an oil change. It's a figure that can also set a timeframe, such as every 1,000 miles or month, every 3,000 miles or three months, and so on. Yet, other indicators (separate from mileage) indicate that an oil change is coming soon.
- An illuminated dashboard warning light
- Excessive black-colored vehicle exhaust
- Increased engine noise
- Dirty oil with a gritty texture (engine oil usually is silky smooth and caramel colored)
- Engine shaking during idling
- Declining oil level (a leak could also be the cause)
Oil is the lifeblood of a car's engine, so it's essential to be aware of when an oil change is needed, including outside a recommended maintenance schedule.