Castrol Axle Z Limited Slip 90 is a mineral oil based gear oil which is suitable for use in limited slip differentials in cars and commercial vehicles where API GL-5 oils with specific limited slip friction performance is required. It can also be used in conventional differentials.Suitable for use in limited slip differentials in cars and commercial vehicles where API GL-5 oils with specific limited slip friction performance is required; it can also be used in conventional differentials. It is approved by ZF for use in their multi-disc wet brakes and self-locking differentials used in a range of commercial vehicle applications including axles in off-road and agricultural equipment.