My mother, when she was alive, asked her most trusted mechanic if she needed any type of additives, other than the regular oil changes. The mechanic, who later moved up the ranks into management in the dealership where he worked, said that she didn't need to put extra aditives to the oil or gas, just use the oil recommended by the manufacturer, and the type of gasoline recommended for the automobile, and she drove her cars for many, many miles, and years and years with regular maintenance oil change, and what the manufacturer required for the warranty of her cars. Someone bought her last automobile that she owned, and it is still going strong, almost 100,000 miles on it, as of last report.