API engine oil ratings

(Image/Summit Racing)

API oil ratings are the various classifications of engine oil set by the American Petroleum Institute, an organization that has been classifying oil since the 1930s.

Because of radical additive changes over the years within the motor oil industry (much less zinc, and new, more highly concentrated detergents), several engine oils manufactured today are incompatible with older engines, and similarly, several older engine oils shouldn’t be used on modern engines (or be used at all).

What are API ratings, how are they categorized, and how can they help you ensure the safety of your engine?

Find out by checking out this video where Summit Racing tech adviser Carl Pritts breaks it down for us.