Written By: Corey Foy

With 40 years of experience in the lubricants industry, we have heard a lot of crazy things about engine oil. In this blog, we will highlight 5 of the most common myths we've heard and correct them for you.

Myth #1: Mixing Synthetic and Conventional Oil is a Big No-No

While it's generally recommended to stick to one oil type (synthetic or conventional), in a pinch, mixing small quantities of different oils won't harm your engine. However, it's best to avoid making a habit of this. If you need to top up your oil, use the same type as your existing oil whenever possible.

Myth #2: Thicker Oil is Always Better

Oil viscosity, indicated by the numbers on the label (e.g., 10W-30), refers to its thickness. Many people believe thicker oil provides better lubrication. The reality? Thicker oil can impede cold-weather engine startup and reduce fuel efficiency. Use the oil grade specified by your car manufacturer for optimal performance.

Myth #3: Synthetic Engine Oil is Only for Fancy Cars

Synthetic oil offers several advantages, including better performance in extreme temperatures and longer intervals between changes. While it might cost a bit more upfront, synthetic oil can potentially save you money in the long run. Consider your driving habits and consult an expert to see if synthetic oil is a good fit for your car or fleet.

Myth #4: Black Oil Means Bad Oil

Oil naturally darkens over time as it collects dirt and grime from your engine. This doesn't necessarily mean it's time for a change. Rely on your car's oil life indicator or follow the manufacturer's recommendations for oil changes. Don't throw away perfectly good oil just because it looks a little scary!

Myth #5: Every 3,000 Miles, Like Clockwork

This one might sound familiar. Traditionally, oil changes were recommended every 3,000 miles. However, advancements in both engine oil technology and car manufacturing have rendered this a thing of the past. Modern synthetic oils last longer, and many cars boast oil life monitoring systems that indicate the optimal change interval. Always refer to your owner's manual for specific recommendations.


Hopefully we were able to clarify any misconceptions you may have had about engine oil. However, always consult your owner's manual or an expert before making a big decision about your vehicle's lubrication.

If you want to browse 49 North's lineup, check out our online store here. Alternatively, if you wanted more information about using synthetic oil in older vehicles, check out this blog here.

Lastly, for any questions please call 1.800.463.0354 and speak to our Technical Specialist - Corey Foy or email info@49northlubricants.com.