Castrol Optitemp PL 3 is based on a lithium soap and mineral base oils, blended with a unique extreme pressure and anti-wear additive package, which has been specifically formulated for compatibility with automotive axle-transmission fluids. Castrol Optitemp PL 3 is approved for use as a first fill grease of bearings mounted in oil lubricated automotive axletransmissions from AUDI, to ensure proper lubrication during start-up, eliminating premature failures.