The American Petroleum Institute (API) has cautioned those who purchase engine oil in bulk to find ways to know they are receiving the correct brand and viscosity grade, such as by checking for authentic API certification, according to a press release.
API works throughout the entire supply chain to ensure all parties handling the product are abiding by the requirements outlined in API 1525A - Bulk Engine Oil Chain of Custody and Quality Documentation–from the oil manufacturer, to the blender, to the transporter/distributor, to the installer.
However, there are products in the market that falsely claim to have API licensing. To counter this, API has the Aftermarket Audit Program, which tests thousands of samples of packaged and bulk engine oils to determine if they are indeed meeting the standards they claim to.
API also warns to be aware of older engine oil standards that are obsolete, as there are many products on the market that meet older performance categories but should not be used. A performance category is considered obsolete when the test methods needed to verify its quality are no longer available, such as a type of engine or necessary hardware being discontinued.