A gear box assembly includes an outer housing and a gear box shaft at least partially disposed in the outer housing. The gear box shaft includes an interior region, a reservoir dam that separates the interior region into a reservoir volume and a spline volume and one or more gear box shaft venting holes formed through the gear box shaft near an end thereof. The assembly also includes a regulator disposed at least partially within the gear box shaft, the regulator including one or more regulator vent holes, wherein at least one of the regulator venting holes is in fluid communication with one of the one or more gear box shaft vent holes.