March 15, 2026 BY
IN Auto Parts

Driveline fluid selection

Driveline fluids, like engine oils, are approved to industry standards such as API, SAE J2360 and MT-1 performance levels. These leading industry bodies and certifications determine the minimum requirements for fluids used in the majority of vehicles

API Service Designations in Current Use

API GL-4: Lubricants intended for axles with spiral bevel gears operating under moderate to severe conditions of speed and load, or axles with hypoid gears operating under moderate conditions of speed and load.

API GL-5: Lubricants intended for gears, particularly hypoid gears, in axles operating under various combinations of high-speed/shock load and low-speed/high-torque conditions.

API MT-1: Lubricants intended for non-synchronised manual transmissions used in buses and heavy-duty trucks.

SAE J2360: Lubricants satisfy and exceed the requirements of API GL-5 and contains performance requirements that exceed those of API Category GL-5. For example, SAE J2360 has a requirement for elastomer compatibility and gear cleanliness after oxidation, that are not contained in API GL-5.

Why do oem defines their own standards?

OEMs are increasingly working with lubricant companies to define their own standards for lubricant performance. These fluids are tailored specifically for the components they manufacture. These standards ensure the lubricant delivers superior performance as they are developed for the engine or component manufactured by the OEM. Castrol has partnerships with major OEMs. This provides Castrol with an opportunity to begin developing lubricants years in advance of the release of a component when it exists only as a drawing.

This approach gives Castrol’s Lubrication Engineers a unique insight into the tribology and specific requirements of the components so they can deliver a product that maximises performance and extends component life. This is Castrol Co-Engineering! To secure lubricant approvals often requires lengthy field trials that can last for up to five years.

Why its important to select right fluid?

With the continuous evolution of cars’ technology over the past years transmissions have become more complex, demanding more technologically advanced fluids to ensure vehicle reliability.

Getting the right oil for your vehicle is key to ensuring drivelines operate as they are designed to and get the maximum protection under demanding conditions. Using the right oil Castrol, with over 100 years of experience in developing transmission and axle fluids and being the choice of many leading car and transmissions manufacturers for factory-fill products, offers a complete range of products which can meet your car’s requirements.

Automatic transmission reveal. Components such as these can be protected using an OEM approved driveline lubricant.

Fill for life fluids

OEMs are working to improve fuel efficiency and provide quality drivability. This has led to the development of OEM service fill specifications for driveline products. As competition for car sales increases, “filled for life” becomes a strategy to reduce the cost of ownership of a vehicle and improve its environmental impact by removing the need to change the oil, filters and screens in manual and automatic transmissions and in differentials and cooling systems. Typically, these filled for life fluids are extremely high quality synthetic oils or long life coolants with the relevant OEM approval.

CastrolL Transmax, Smooth Drive Technology

Whether a car is automatic or manual, Castrol TRANSMAX range has the right transmission fluid for the vehicle, providing enhanced protection to all moving parts which enables longer transmission life.

The advanced Castrol TRANSMAX range features Smooth Drive Technology™ with active control molecules that automatically adjust their friction level with changing pressures and speed. This ensures the transmission is constantly served the right level of friction at any given moment – protecting the parts and delivering a smoother drive for longer.you are providing the correct recommendation.