quote:I agree, but for one thing. I don't think the fuel efficiency test is required for SL. Check out any SL 10w40 or higher grade oil (or any grade of the so-called high mileage oils) and it will not have the starburst, nor will it have the words "Energy Conserving" in the API donut. A 10w40 can't pass the test as the test oil a supplier has to beat is a 5w30 synthetic.
Originally posted by TooSlick: Organic friction modifiers are used in gas engine oils to help them pass the "Sequence IVB", fuel efficiency test. This test is a requirement for SL and/or GF-3, gas engine oils and allows them to display the "starburst" that you also find in owners manuals for new vehicles. This is an attempt to influence buying habits and get folks to use low viscosity, 5w-20/5w-30 oils in order to oprimize fuel efficiency.