Remember when just about every engine used 10W-40 motor oil, which you could find at every service station when you needed to top off? Heck, remember service stations? Both are dying breeds these days. One reason modern engines run so efficiently is because of their tight tolerances between rotating parts, tolerances that require lighter-weight oils to keep from gumming up the works.
Americans in 2015 wasted some $2.1 billion buying premium fuel they didn’t need
According to the Department of Energy, running 10W-30 (or worse, our venerable 10W-40) in an engine designed to run 5W-30 can reduce fuel economy 1 to 2 percent. Even being off by a little—using 5W-30 when 5W-20 is called for—can impact fuel economy by some 1 to 1.5 percent. Check your owner’s manual for the oil grade recommended by the manufacturer.
On a related note, for newer trucks, the old rule of thumb about changing the oil every 3,000 miles is outdated, too. Modern engines are designed to go 5,000 miles or more between oil changes. Again, make friends with your owner’s manual to see what interval is recommended based on how you use your truck. There’s no need to buy oil more often than you have to.
Don’t Waste Money on Premium Fuel
Photograph by Drew Hardin
Unless your owner’s manual specifically recommends running high-octane fuel, there is no need to spend money on more expensive gasoline.
Premium fuel, frankly, is misnamed. It is not a better- quality fuel, it simply has a higher level of octane* than mid-grade or regular fuels. Unless your vehicle manufacturer recommends using premium, there is no advantage to using premium fuel in an engine that doesn’t require it.
The AAA confirmed this in a series of engine dynamometer tests in 2016 Their research also turned up a startling statistic: Americans in 2015 wasted some $2.1 billion buying premium fuel they didn’t need.
(*The octane rating is a measure of how much the fuel can be compressed before it spontaneously ignites. High-performance engines, or engines that are turbo- or supercharged, often require high-octane fuel because of the higher compression ratios in their cylinder heads. Without the higher octane, the gas in the cylinder could pre-ignite, causing knock or pinging that could damage the engine.)