Description
Premium gear oil for manual transmissions and differentials.
Castrol 80w-90 GL4 is a high-performance gear oil specifically formulated to meet the demanding requirements of manual transmissions and moderately loaded axles. The GL4 classification indicates it contains the right level of extreme pressure (EP) additives to protect gears without being overly aggressive on yellow metals (brass/bronze) often found in synchronizers.
This sophisticated balance is critical since too much EP additive can attack synchronizer components, while too little won’t adequately protect gears under high loads. The 80w-90 viscosity rating means it flows sufficiently at lower temperatures for proper cold-weather shifting (the “80w” winter rating) while maintaining a robust protective film at higher operating temperatures (the “90” high-temperature rating). This dual nature ensures protection across various driving conditions.
The formulation includes specialized additives that create a microscopic protective layer on gear surfaces to prevent metal-to-metal contact during the extreme pressures of gear meshing. Its superior shear stability ensures it maintains viscosity even under the high-shear conditions experienced in gear systems. This oil’s thermal stability helps resist breakdown at high temperatures, while its corrosion inhibitors protect metal components from moisture and contaminants.
The 5L container provides sufficient oil for multiple differential or transmission services. This premium gear oil helps ensure smooth, quiet operation while extending the service life of critical drivetrain components.
