Castrol has launched Castrol ON EV Transmission Fluid W3, a next-generation, full synthetic EV transmission fluid that can help extend the life of the drivetrain system and helps EVs go further on a single charge.
It is engineered specifically for electric vehicles with wet e-motors – including those from Leapmotor, MG, Polestar, Rivian, Telsa and Volvo – where the electric motor operates immersed in fluid.
Castrol ON EV Transmission Fluid W3 is designed to help optimise motor efficiency and performance through reduced friction, leading to reduced operating temperatures. In addition, the fluid demonstrates high levels of thermal and oxidative stability, which helps maintain performance over an extended service life.
The improved gear protection and strong thermal characteristics, combined with the fluid’s low-temperature pumpability and cold-flow properties, helps to deliver reliable operation in cold climates. A high viscosity index means the fluid delivers consistent performance across a wide temperature range, supporting reliable operations in diverse driving conditions.
Castrol ON EV Transmission Fluid W3’s di-electric properties include low electrical conductivity, high resistance and a high breakdown voltage, all helping to protect sensitive electrical components within the drivetrain. It also provides protection against copper corrosion to aid the durability and reliability of the electric motor and associated hardware.
Vincent Panel, Head of Product & Communications – Europe at Castrol, said: “Electric vehicles demand a new generation of fluids, and that is why Castrol ON EV Transmission Fluid W3 has been formulated to meet the unique challenges of wet e-motor systems, enhancing efficiency, protection and temperature control.”
Castrol ON EV Transmission Fluid W3 is part of the Castrol ON range, developed to support the transition to electrified mobility with fluids, greases and thermal management solutions developed specifically for electric vehicles.
Castrol advises vehicle owners and service professionals to always consult the vehicle manufacturer’s recommendations to ensure the correct fluid is used for each specific electric vehicle application.
To find out more about the Castrol ON range, visit: www.castrol.com.

