A planet gearbox for connection to a carrier (90, 92) of an epicyclic gearing arrangement that has only a single input and a single output and that includes a sun gear and a ring gear surrounding the planet gearbox and the sun gear, the planet gearbox comprising: a support pin configured to be fixed to the carrier and defining a cylindrical outer surface that is radially equidistant from a central axis that extends in an axial direction, the support pin is further defined as a hollow cylinder by a cylindrical inner surface disposed opposite the cylindrical outer surface, the support pin includes a plurality of oil feed holes, each oil feed hole extending through the support pin between the inner and outer surfaces (101, 125) of the support pin and defining an exit opening at the outer surface of the support pin; an inner ring defining a cylindrical inner surface that is non-rotatably connected to the cylindrical outer surface of the support pin, the inner ring defining an outer surface that defines at least one track, each track defined in the outer surface being configured to receive and rotatably guide therein a respective plurality of cylindrical rollers; a respective plurality of cylindrical rollers rotatably disposed within each respective track of the inner ring; an outer ring defining an inner cylindrical surface contacting each respective plurality of cylindrical rollers, the outer ring defining an outer cylindrical surface that defines a gear tooth surface that is configured to mesh with both the sun gear and the ring gear; for each respective track, a respective roller cage disposed between the inner ring and the outer ring; characterized in that a network of interconnected grooves (121, 122, 123) is provided in one of the cylindrical outer surface of the support pin and the cylindrical inner surface of the inner ring, wherein each oil feed hole through the support pin is disposed to intersect with the network of grooves (121, 122, 123). a support pin configured to be fixed to the carrier and defining a cylindrical outer surface that is radially equidistant from a central axis that extends in an axial direction, the support pin is further defined as a hollow cylinder by a cylindrical inner surface disposed opposite the cylindrical outer surface, the support pin includes a plurality of oil feed holes, each oil feed hole extending through the support pin between the inner and outer surfaces (101, 125) of the support pin and defining an exit opening at the outer surface of the support pin; an inner ring defining a cylindrical inner surface that is non-rotatably connected to the cylindrical outer surface of the support pin, the inner ring defining an outer surface that defines at least one track, each track defined in the outer surface being configured to receive and rotatably guide therein a respective plurality of cylindrical rollers; a respective plurality of cylindrical rollers rotatably disposed within each respective track of the inner ring; an outer ring defining an inner cylindrical surface contacting each respective plurality of cylindrical rollers, the outer ring defining an outer cylindrical surface that defines a gear tooth surface that is configured to mesh with both the sun gear and the ring gear; for each respective track, a respective roller cage disposed between the inner ring and the outer ring; characterized in that a network of interconnected grooves (121, 122, 123) is provided in one of the cylindrical outer surface of the support pin and the cylindrical inner surface of the inner ring, wherein each oil feed hole through the support pin is disposed to intersect with the network of grooves (121, 122, 123).