How often should you change your synthetic oil?

Before today’s automobiles, there was an easy way to know when to change your oil every 3,000 miles.  Cars were built tough, simple, uncomplicated, with no computers and horsepower galore. The engine blocks were iron-clad beasts.  Internally the engines were just as rugged.  These engines needed good clean oil to keep them running, and the oil needed to be changed often.

Conventional oil was the only option, and you needed to change your oil every 3,000 miles for maximum engine protection.  The filters and oil of yesteryear were not the products of today.

Oil and Engines in the 21st Century

The oil refining process, technologically advanced engines, synthetic oils like AMSOIL, and advanced filter technology have changed oil changes and general vehicle maintenance.

So let’s assume that your vehicle has an oil change monitor.  This monitor matches up with the manufacturer’s recommendation on how often you should change the oil.  Now, this seems simple; follow the advice, right?   This “recommendation” is merely a guideline, and it is essential to look deeper at why this could change how often you choose to change your oil.  Driving conditions, driving style, and environmental conditions all play a factor in the health of your sophisticated, precision-machined engine today, and this is where synthetic oil begins to grow in popularity and quite frankly makes sense.

Engine Parts

Precision manufacturing of engine parts was a loose term years ago, where today, things are made extremely precise and exacting.  Thinking back to the early 20th century, if you owned one particular brand of motorcycle, you would have to put a pan under the engine to catch the dripping oil, and that was commonplace.  Today, things are tighter, exacting, and less forgiving.  Engine technology has improved with the invention of materials to handle higher heat, faster RPMs.  Engineers have improved the overall design of the engine, housing, and ignition systems, improving fuel economy, lessening oil consumption, and gaining exceptional performance.

With these profound changes in engine composition, the need to change your oil is different for many applications.  Engine manufacturers test the engines in hi-tech laboratories and will recommend a specific viscosity and change interval.  More and more manufacturers recommend that synthetic oils be used vs. conventional oil due to their fantastic wear properties.

When to Change Oil?

OK, great!  I know what you are thinking, you’ve answered the question of when to change my oil?  Yes, in a nutshell, refer to your owner’s manual and follow their recommendations.  Today, manufacturers may cite 5,000 – 7,500 miles in the owner’s manual, and now a few automakers say every 10,000 miles.

Synthetic motor oil is much different and can extend drain intervals without dad’s conventional oil damaging properties.  To check, you say?  Yes, it is accurate, and it’s back to the scientific technologies of today.  The engineers at AMSOIL, for example, have perfected a blend of Signature Series motor oil that, with their patented filter, can go up to 25,000 miles or one year.  This is astounding!  All due to the properties of highly refined synthetic motor oil.

Synthetic oil is formulated and distilled to a place where on a molecular level, all those microscopic fellows are the same size making them very slippery.  You couple that with additives that clean and fight deposits and wear; you have one heck of engine oil.

Now back to the driving conditions and environmental factors.  These factors do change the lifespan of your oil and are something to consider when deciding on how often you are inconvenienced by doing an oil change.

Factors to Consider

Here are some factors to take into consideration when determining the number of miles or time between oil changes:

  • Driving daily, less than 10 miles per trip.
  • Daily commutes in frigid weather.
  • Using your vehicle for towing, mainly uphill.
  • Dusty environments and driving on a dirt road regularly.
  • Turbocharged engines.
  • Diesel powered vehicles.
  • Daily stop and go driving.
  • Regular highway driving in hot summer months.
  • Condition and age of your vehicle.

Driving Conditions

You can see that many of us drive in one of these extreme conditions effects and engines’ oil lifespan.  Oil loses effectiveness as it breaks down from excessive heat.  This causes oxidation which changes the oil’s chemistry.  It prevents the oil from cooling, lubricating, and protecting the engine.  Sludge begins to form, which can clog the narrow oil passages.  Oxidation also increases the oil’s viscosity which negatively affects oil efficiency.  Oil manufacturers incorporate additives that do specific jobs, like holding dirt, soot, and other contaminants.

Change the oil when additives are depleted.   If you choose conventional oil, you may need to stick with the 3,000-mile rule, especially if you drive in the conditions listed above.  However, with synthetic motor oil, you can enjoy the benefits of an extended drain interval because of how synthetic motor oil is made. Here are some reasons why synthetic oil like AMSOIL performs much better:

  • Additives help prevent corrosion inside the engine.
  • Added film strength keeps components coated between engine startups.
  • Significantly reduces the wear caused by friction on engines that run at higher speeds.
  • Does not break down thermally.
  • Extends the oil’s life by lowering the engine operating temperature.

Now, synthetic oil is more expensive than conventional oil, but the adage “you get what you pay for” really does apply here.  Using a product like AMSOIL will save you money by lowering the number of oil changes you will need in a year and helping our environment by reducing the quantity of oil used in your vehicle each year.


For most everyone, we need to follow the manufacturer’s recommendation.  This fundamental guideline will keep the engine running strong for years.  For added protection, using a fully synthetic motor oil such as Amsoil will upgrade your overall engine protection and increase performance.  When using a high-quality full synthetic motor oil, you can extend your drain interval with confidence, knowing that the oil can withstand the rigors of today’s engines and driving environment.

AMSOIL XL has a one-year or 12,000-mile drain interval that fits many drivers.

Amsoil Signature Series Oil offers up protection to last 25,000 miles or one year, depending on the vehicle.

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