When you’re buying oil and comparing Evinrude XD 100 and XD 50, do you really know what the difference is? The XD100 is more expensive, so it’s fairly obvious that it is superior in some way. Virtually all synthetics start with the same base structure, especially variants of the same manufacturer. The difference is in the additives.
Oils that are more expensive contain more additives, which enhance the performance of your engine. While standard grade oil will provide lubrication and protect your engine, premium oils work to eliminate ash, smoke and odor too. They also can improve the longevity of your motor.