GPM TRX4022B rear knuckle arms for the Traxxas TRX4 are CNC machined from 6061 T6 aluminium to deliver tight tolerances, long term durability, and consistent inner gear support. These parts are designed to minimise deflection under load and maintain accurate gear meshing, helping reduce premature wear in demanding driving conditions. The machined surfaces promote dependable contact and simplify setup for tuners seeking reliable upgrade hardware.