A reader asks: “Despite the fact that AMSOIL Synthetic engine oils are designed for very long oil change intervals, my personal preference is to change my oil at the mileage suggested by my owners’ manual. As I’m changing my oil more often than most AMSOIL users would, is it worth it to use AMSOIL or is it a waste of money? An honest answer would be appreciated.”

Answer: Well that is an honest question and hopefully our answer is adequate. AMSOIL offers three distinct series’ of synthetic motor oils for modern automotive service, with only one having an exceptionally long service interval. It should first be noted that today’s cars and trucks have service intervals that are far longer than those recommended just a few years ago. Two of these three AMSOIL series’ have recommended service intervals that are quite in line with the suggested oil change period in your manual. Let’s look at each of these engine oil product lines and how they fit into today’s maintenance practices.

AMSOIL OE Series- This is AMSOIL’s entry-level synthetic oil that is designed for the budget-minded car owner and the quick lube market. The OE Series is designed for the drain interval as prescribed by your manufacturer. When you have reached the mileage or time threshold suggested by your manual, you change OE Synthetic Oil. It’s that simple. This also applies to electronic oil change monitoring systems. As oil change intervals and especially oil change monitoring systems can have widely varying intervals, AMSOIL OE Series is over-built to withstand the longest of these possible scenarios. AMSOIL OE is available in 0W-20, 5W-20, 5W-30 or 10W-30.

AMSOIL XL Series- This is AMSOIL’s “middle” series of synthetic motor oils and it has a recommended service interval that is every bit as simple as that suggested for OE. The XL Series oil change recommendation is 16,000 kilometres (10,000 miles) or 6 months. When you reach one of these thresholds, you simply change XL Motor Oil. In the case of vehicles with oil change monitors, the electronic minder may take you beyond the 10,000 mile/6 month threshold. XL is also overbuilt to withstand the longest interval that your monitor may take you. AMSOIL considers these factors when formulating their products. AMSOIL XL is available in 0W-20, 5W-20, 5W-30, 10W-30 or 10W-40.

AMSOIL Signature Series- This is AMSOIL’s premiere synthetic oil line and it boasts an oil change interval that strains credulity for some observers. AMSOIL warrants that Signature Series is capable of being in service for a whopping 40,000 kilometres (25,000 mile) or one year. Keep in mind that AMSOIL offers several footnotes with this recommendation and you’ll find that this drain interval only applies to vehicles that see mainly long trips. Vehicles that see service such as regular short trips, towing, dusty conditions are relegated to a 24,000 kilometre (15,000 mile) or one year suggestion.

Regardless, these are pretty tall claims. Having been involved with the company since 2001, we can attest that AMSOIL tends to over-deliver on their claims and have over 40 years of stellar performance to back it up. Obviously very few people log 40,000 kilometres per year, but many customers do indeed change their oil every 12 months with this series. Many (including us) are happy to use a motor oil that is not cause for concern if it is left in the crankcase until we have time to change it. We tend to change our oil every 7 or 8 months, regardless of the mileage on the clock. This may be as little as 8000 to 12,000 kilometres. But it is nice to know that we can leave it for much longer if we don’t have time to deal with it.

Even if one were to simply change AMSOIL Signature Series at the OEM oil change interval (and many customers do this), this is the industry’s most elite motor oil series for gasoline engine service. It may be overkill, but engine oil is a relatively small automotive input cost. AMSOIL Signature Series is available in 0W-20, 5W-20, 0W-30, 5W-30 or 10W-30.

For more info on any of these products, visit our Synthetic Engine Oil product page.

So Are the Longer Drain Synthetic Oils Worth it?

Now that we’ve laid out the general description of each series, we can discuss the benefits and features of AMSOIL Synthetic Oil. This is boilerplate stuff, but it sheds further light on how these products are not only worth it, but a tremendous, cost-effective value. These include:

  • Reduced friction
  • Optimised gas mileage
  • Powerful wear protection
  • Dependable cold weather starting
  • Consistent protection in hot weather and under heavy load
  • Reduced oil consumption

All three AMSOIL lines provide these benefits, with the gains improving as one moves from OE to XL and then onto Signature Series.


The bottom line is that you do not have to feel obliged to max out AMSOIL’s long drain capabilities to get full value from the products. It’s is nice to know that you are using an elite synthetic in your engine and could push the drain interval longer, if you chose to do so.

We can offer any of these products at wholesale to add further value to these synthetic engine oils. Request a price list using the contact form on your upper right or call us at 1-800-748-5781.