Are Engine Additives Beneficial?

Are oil additives such as Slick 50, Duralube, Prolong, and all the others on the market of any benefit? The short answer is NO. I never have and never will add any oil additive to my engine. If you purchase and use a good name brand oil that is certified to meet API standards, then why add some product with dubious quality to that expensive engine? The major oil companies spend millions of dollars developing and testing their products. Their oil contains all the additives it needs. These oil additive companies spend a fraction of this on development and most of their money on trying to convince the consumer their product is the cure all for everything. They want you to add an unapproved additive to the approved oil already in the crankcase. See the flaw in this thinking. Stay away from oil additives. You may have noticed I recommend a product called Seafoam Motor Tune. Seafoam is not an oil additive but rather a cleaner, and fuel stabilizer. Click the product name to read all about it. Rather than discuss these worthless products in detail here, click the title and you will be able to read all about this subject at a respected website.