The transmission oils in this series were developed specifically for transmissions in Caterpillar equipment and vehicles. They are formulated to be compatible with the materials used in these transmissions, including metals, seals, and clutch friction materials, and to withstand their typical operating demands. The friction and lubrication properties of CATO-4 oils provide performance across the operating range of transmissions in earthmoving and heavy equipment, including under maximum load. They help reduce transmission wear and extend service life while protecting components against rust and corrosion.