Synthetic vs. Conventional: What’s the Difference?

Motor oil is considered one of the most important fluids in your car, and changing it is critical to maintaining a healthy engine. Some experts, including Consumer Reports, even refer to motor oil as the lifeblood of a vehicle. Consumer Reports also notes that motor oil does more than lubricate the moving parts of an engine — it cleans the engine and keeps it from overheating, too.

Keeping these facts in mind, it is easy to understand why changing the oil in your car is so important. However, there is some confusion about the difference between conventional and synthetic oils. In this post, we’ll shed some light on the difference between the two to help you decide what’s best for your vehicle.

The Science of Synthetic

According to Valvoline, both synthetic and conventional motor oils are derived from crude oil, but synthetic goes through a synthesis process that breaks down or assembles molecules to make them the same size. Oil molecules that are close in size have a high film strength, which results in increased longevity and the ability to handle extreme temperatures without breaking down.

Better Gas Mileage

Who doesn’t want better gas mileage? Synthetic oil is stronger and more slippery, allowing your engine to run more efficiently, and Valvoline says an efficient-running engine can save you money at the pump.

Fewer Oil Changes

Between balancing work and your personal life it can be difficult to find time for an oil change. Luckily, synthetic oil lasts longer than conventional oil, and that can mean fewer oil changes. In fact, explains that because synthetic oil doesn’t break down as easily, it can last up to 12,000 miles.

Reliable Year-Round

Pep Boys reports on its website that synthetic oil maintains its consistency better than conventional oil in extreme temperatures, which can help your engine perform at its absolute best. Simply put, synthetic runs better under high heat and extreme cold.

Consider the Cost

One thing to keep in mind when considering synthetic oil is cost. Synthetic can be up to double the cost of conventional oil. But, argues that because you change your oil less frequently, you won’t notice a difference in how much you’re spending on oil each year. Plus, you get all the engine benefits of using synthetic oil.

If you aren’t sure what’s right for your vehicle, consult your owner’s manual for the manufacturer’s specifications and recommendations. And, if you have any questions about switching to synthetic, consult your local dealer.

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  1. 1
    Robert Waples

    Dear Ally, Can you also please post an article on something that is so simple but is being overlooked? Everyday when I’m on the road I see so many vehicles with brake lights out, tail lights, etc…. From old to very new cars (Even my new dodge had a tail light issue that had to be repaired.) I try to encourage everyone to safety check there vehicles at least once every 3 months to ensure that all lights are working, check their air pressure in the tires and of course check their own fluids or at least have these items checked at their dealership. It really amazes me how many automobiles I see on the road that have these issues. Road Safety is everyone’s responsibility. THANKS!

  2. 3

    Agreed on all the benefits of synthetic oil. The benefits of synthetic oil are numerous and overwhelming because Synthetic Base Stocks i.e. PAO’s, Esters & AN are tailor made from molecular building blocks using pure ingredients so do not contain any of the impurities found in crude oils that end up in Conventional Mineral Oils.

  3. 4

    This article really helped me to understand the difference between synthetic and conventional oil! Thank your for this article.

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