Honda says to use 10w-30. After putting in a SC in the S would anyone suggest running 5w-30 or 15w-50 full synthetic? Can soneone explain the meaning of these numbers.

 

Comptech recommends RedLine 10w-40 synthetic for use with their SC.

 

The numbers are an indication of "viscosity" (or thickness in plain language). The higher the number the thicker the oil, the slower it pours or flows. The first number that has the "W" after it means "winter" (or it's viscosity when it is stone cold). You need a lower number for better cold cranking ease. Once the oil heats up, it then takes on the characteristics of the higher number. These oils are catagorized as "muti-grade".