Overtake Rear Differential Bushing InsertMore connection. More control. Less drivetrain flex. Your rear differential is mounted using soft factory rubber that flexes and twists under load. That movement absorbs energy, dulls feedback, and reduces how directly power is transferred to the wheels. The OVERTAKE Subaru WRX and STI Rear Differential Bushing Inserts solve this by reinforcing the factory mounts with performance rated 80A durometer urethane, significantly reducing unwanted movement.