How Does Synthetic Motor Oil Increase Fuel Economy?

Gas pump, fuel economyAlthough gas is hovering around only $2.00 per gallon these days, increasing fuel economy is still a top priority for most automakers, due in large part to more strict corporate average fuel economy (CAFE) requirements on the horizon.

One strategy automakers are using is widespread use of synthetic lubricants. How do synthetics increase fuel economy compared to conventional lubricants?

Reducing viscosity increases fuel economy

At one time, most passenger cars/light trucks used 10W-40 motor oil. Then it was 5W-30. Today, many vehicles call for 5W-20 and 0W-20 oils. And an even lower viscosity, 0W-16, is on the horizon for certain newer vehicles.

The lower the oil’s viscosity – defined as its resistance to flow – the more readily it will flow. Imagine a jar of honey and a glass of water. Stirring water with a spoon requires less energy than stirring honey. The same principle applies to your engine and motor oil. Lower-viscosity oils are easier to pump through the engine and offer reduced resistance to moving engine parts, increasing fuel economy.

Why do synthetics offer an advantage in reducing motor oil viscosity?

Formulating a 0W-XX motor oil using only conventional base oils is extremely difficult at best, if not impossible. While formulators can achieve the 0W rating, the oil will vaporize more readily at higher temperatures and fail other required industry tests. Simply put, formulating lubricants is a give/take, and conventional base oils don’t provide near the performance as synthetics, requiring formulators to give up too much required performance in one area to gain it in another. In this case, conventional oils have to give up too much high-temperature performance to achieve the 0W rating.

Better cold-flow ability

Synthetics’ improved flow during cold starts also improves fuel economy. Since they don’t contain waxes, which are inherent to conventional oils, they don’t thicken as much when your vehicle sits overnight. In the morning, when you start your vehicle and drive away, the motor oil, transmission fluid and gear lube don’t require as much effort to circulate. This results in less wasted energy and improved fuel economy.

It’s important to note that “cold” doesn’t only apply to us northern folks. “Normal” operating temperature for a vehicle can be up to 235ºF, and anything below that is considered cold to your engine. So even down south at the height of summer, synthetics’ improved cold-flow can still help improve fuel economy.

At AMSOIL, we’ve conducted multiple fuel-economy field trials. One of them revealed a 6.54 percent increase in fuel economy using AMSOIL synthetic lubricants compared to conventional oils in class 8 diesel trucks, which equals major savings for trucking fleets. We’ve also fielded multiple testimonials over the years from satisfied AMSOIL users who have experienced increased fuel economy (my own parents among them).

Gas probably won’t stay at $2.00 per gallon forever – prepare yourself by switching to synthetic lubricants if you haven’t already.

Related Posts

Comments

  1. I want to change my oil in my 2003 FORD F 150 to Synthetic oil. Do i need to do anything other than drain the old oil out and put the new in ?? it’s got the 5.4 liter and if it can help with performance I want Synthetic cause the miles are getting up there.

    1. Hi Robert,

      No, you don’t have to do anything special prior to switching to synthetic motor oil. Just drain the oil, replace the filter and refill. You can use an engine flush to remove accumulated deposits if you want. Check out this article we wrote on this topic.

      Thanks.

  2. Hello Jim,

    John made some good points …

    Over in the European line of oils,

    Amsoil’s Mid SAPS 5.40 — AFLQT

    Meets the VW 501.00 and 505.01
    BMW Longlife-04
    Mercedes Benz 229.52
    Porsche A40

    And GM’s Dexos 2 higher performance standards.

    In my opinion, any oil capable of being used in gas or diesel powerplants
    With turbo or without –
    Must be one stout engine lubricant.

    I use it in all my customers’ Turbo Diesel and Turbo Gas engines.
    Selling the oil change by the first fill and doing a case and 2 filters
    for after the fact – when maybe they can not get back to me – when we
    are on different schedules or something.

    So, I’m just saying … AFLQT –
    is a great all season engine oil for many engines.
    Unless folks are traveling like a salesman –
    2 oil changes a year with this 5.40 ought to give you
    great protection and an increase in fuel economy as well.

    Take care,

    1. Hi Jim,

      Full synthetic motor oils don’t contain the conventional base oils found in synthetic-blend products, meaning they typically provide improved wear protection, engine cleanliness and fuel economy, among other benefits. In addition, there’s no definition for a “blend” – it could contain anywhere from a drop to mostly synthetic base oils, so it’s tough to predict performance.

      Also, the GM dexos1 specification doesn’t stipulate the motor oil you use must be a synthetic-blend. In fact, plenty of high-quality full synthetic motor oils available carry the dexos1 spec, including AMSOIL Signature Series, AMSOIL XL and AMSOIL OE Synthetic Motor Oils. Be sure to use the correct viscosity for your XTS.

Leave a Reply

Comment:
Name:
Email:
Website: