Yokomo RP-08510KA Racing Performer Ultra diff oil #10000, silicone gear differential oil for RC gear differentials  [RP-08510KA]

High-viscosity silicone diff oil

This Racing Performer Ultra diff oil is an RC-scale gear differential fluid formulated to support higher drivetrain loads that come with modern LiPo batteries and brushless motors. The #10000 grade provides a high-viscosity silicone base intended to stabilise internal damping so the differential maintains predictable behavior under sustained stress.

In practical use the oil's role is to control torque transfer between wheels, smoothing engagement during acceleration and balancing slip through cornering. A heavier silicone fluid such as this reduces abrupt changes in diff action, helping maintain traction feel from the opening laps through longer runs.

Service guidance: when replacing differential oil, fully drain the old fluid, clean the internal gears and housing, inspect seals and bearings for wear, then refill to the manufacturer recommended level and reassemble. After refilling, run a few moderate laps to allow the oil to distribute and settle before returning to full competition pace.

Tuning note: swapping to a higher-number diff oil like #10000 increases coupling between axle outputs and can reduce spin under power, so adjust driving technique and suspension settings accordingly to retain desired handling balance.