Gear oil with Jaso approval

JASO

— oils that comply with one of the JASO standards.

These standards are applied by Japanese manufacturers of cars with automatic transmission. Such cars have more stringent oil requirements than those provided by the Dexron and Mercon standards, which is why a separate family of standards had to be introduced. The most popular versions of JASO in modern automatic transmissions are JASO M315 and JASO 1A.