CONSTRUCTION
TOYOTA genuine ATF WS is used to reduce the resistance of the ATF and improve the fuel economy by reducing its viscosity in the practical operating temperature range. At higher-fluid temperatures, the viscosity is the same as that of TOYOTA genuine ATF Type T-IV, to ensure the durability of the automatic transmission.
There is no interchangeability between the TOYOTA genuine ATF WS and other types of ATF (D-II, DIII or TOYOTA genuine ATF Type T-IV).