The 30, 38, and 47-inch windmill heads use a durable hub with sealed bearings that do not need greasing.
The 60-inch windmill head uses a heavy duty hub/bearing assembly, and is greased through the spindle and packs both the front and rear bearings simultaneously. We recommend greasing the bearings once a year. The same hub/bearing assembly is used at the pivot point where the vertical and horizontal shafts meet.