Anyone in the automotive repair/fast lube industry will be able to recognize that motor oils are changing to benefit fuel economy targets. In the U.S., it is mandated by the year 2016 all vehicles produced for sale in the U.S. will have an average fuel economy of 35.5 mpg. Manufacturers will be able to reach these targets by combining the fuel economies of their entire fleet to get to that number. For example, a hybrid could have a fuel economy of 50 mpg and a SUV could have 21 mpg but when these two are averaged together it equals the target of 35.5 mpg. The quickest way to get vehicles to this target is through lighter weight and more viscous oils. In the last few years, I have seen Honda go from using 5W20 to using 0W20 in an effort to continue to improve fuel economy. In a recent article I wrote about Ford beginning the use of a 0W10 in Europe.
For customers who continue to insist on using 5W30 or 10W30 oils when their vehicle recommends a lighter weight oil they need to be educated that lighter oils will help the vehicle achieve its desired fuel economy and benefit the performance of the engine in the long run. We all have a role to play in ensuring vehicles get the best performance and it can be as simple as using the correct motor oil.