At that point in time, he develops a sudden interest and soon learns that unbiased factual information is not easy to come by. When petroleum oil was first discovered over 125 years ago the first claims for it started. Of course, the claims and counter claims continue to this day. Along with the oil companies which manufacture the fuels and lubricants there is a whole host of companies which manufacture additives for these products. Over the years, some of these additives have proven beneficial, but, for the most part, additives fall into the snake oil category.
Snake oil can be very profitable.
At one time, the writer asked a service station owner why he carried and recommended a particular oil additive. When it comes to engine oil there really isn't too much to be concerned about. Basically, the API website will give you all the information you need to select the proper oil for your engine. It will also give you a listing of all licensed engine oils by brand name so that you may use the proper grade of your favorite oil. Neither the oil manufacturers nor the automotive manufacturers recommend the use of engine oil additives.