A carrier and at least one pin shaft of a gearbox of a wind turbine and method of manufacturing same includes forming the carrier and the pin shaft(s) as a single part or separate components. Further, the method includes forming one or more voids in the pin shaft(s) and/or the carrier via additive manufacturing. As such, the void(s) is configured to increase flexibility of the pin shaft(s)/carrier so as to improve a load distribution thereof.