Improving fuel economy remains a top priority for most car makers. Vehicle fuel efficiency standards are there to meet, while Australian drivers are feeling the pinch at the petrol pump, with prices in some cities near four-year highs as international supply concerns drive up oil prices.
One strategy car makers are using is widespread use of fully synthetic oils. How do fully synthetic oils increase fuel economy compared to regular oils?
At one time, most passenger cars/light trucks used 10W-40 engine oil. Then it was 5W-30. Today, many vehicles call for 5W-20 and 0W-20 oils. As a signal of things to come, the 2018 Toyota Camry calls for 0W-16 oil.
The lower the oil’s viscosity – defined as its resistance to flow – the more readily it flows. 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 engine oil.
Lower-viscosity oils are easier to pump through the engine and offer reduced resistance to moving engine parts, increasing fuel economy.
Formulating a 0W-XX engine oil using only conventional base oils is extremely difficult, if not impossible. Formulators can achieve the 0W rating, but the oil will vaporize more readily at higher temperatures. It’ll also fail other required industry tests. Simply put, formulating lubricants is a give and take, and conventional base oils don’t provide near the performance as fully synthetic oils. This requires formulators to give up too much required performance in one area to gain it in another.
Fully synthetic oils improved flow during cold temperature starts also reduces fuel consumption. 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 engine oil and transmission fluid don’t require as much effort to circulate. This results in less wasted energy and increased fuel economy.
It’s important to note that “cold” doesn’t only apply to the coldest inhabited place on earth. “Normal” operating temperature for a vehicle can be up to 112ºC. Anything below that is considered “cold” to your engine. So even at the height of summer, fully synthetic oils improved cold-flow can still help increase fuel economy.
Why pay more for petrol? Switch to fully synthetic oils to maximize your KPL (Kilometres Per Litre.