Hardrace Rear Differential Anti-Vibration InsertHardrace subframe anti vibration insert features CNC aluminum construction for precise fitment to the factory differential bushings. By filling the void in the bushings, the inserts capably limit unwanted powertrain movement and twisting when accelerating and shifting, resulting in less vibration and greater power transfer to the wheels. . Anodized CNC aluminum construction . Precise fitment to the bushing voids . Eliminate unwanted powertrain twist &