MB 239.21

Approval MB 239.21 is a Mercedes‑Benz technical requirement for automatic transmission fluids, developed to ensure stable operation of multi‑speed gearboxes, including 7‑ and 9‑speed automatic transmissions (7G‑TRONIC, 9G‑TRONIC) and new 8‑speed models. A fluid that meets MB 239.21 must have a high viscosity index, excellent resistance to oxidation and thermal degradation, and also provide low friction and effective protection against wear of metal gear teeth and friction discs. The specification calls for compatibility with electronically controlled transmission management systems and with the materials of load‑bearing components, including synthetic polymers and metal coatings. Since MB 239.21 does not contain requirements for low‑ash additives, it does not restrict use in engines with DPF or a catalyst, but it guarantees full compatibility with typical Mercedes‑Benz emission‑cleaning systems. When selecting a product on xenum.ua, for example the transmission oil XT‑POWERSHIFT, you receive a fluid that complies with this specification and provides smooth shifting, reduced fuel consumption and long‑lasting transmission reliability.