239.21

Specification 239.21 is an OEM approval for transmission oils developed for automatic gearboxes of heavy trucks and buses. Technically it requires stable viscosity in the range –40 °C…+120 °C, high wear, oxidation and deposit resistance, as well as special friction properties for smooth engagement of clutch packs. This approved formula is suitable for transmission systems ZF Powershift, Allison TES‑295/389, DAF, Detroit Diesel and similar, where compatibility with electronic control and over‑heat protection systems is required. Oils that meet 239.21 do not contain SAPS, therefore they are safe to use with catalysts and DPFs, if the gearbox design allows it. In our catalogue we present two products – XT‑POWERSHIFT and XA‑TRAN DX VI – which fully comply with 239.21, providing reliable protection and optimal transmission efficiency.