A planetary gear assembly having improved planet gear lubrication includes a thrust bearing assembly mounted to the planet gear carrier which provides a friction reducing interface between the carrier and a hub or stationary transmission member. A lubrication dam located radially outwardly of the thrust bearing assembly collects transmission fluid (oil) that has been supplied through a centrally disposed shaft and driven to and past the thrust bearing and into the dam by centrifugal force. Transmission fluid collecting within the dam and between the thrust bearing assembly and the planet gear carrier generates a biasing force which drives the thrust bearing assembly away from the planet gear carrier, thereby ensuring that the bearing position is not indeterminate and positively locating the thrust bearing assembly and providing an annular flow path for the transmission fluid which is then directed into a plurality of axial passageways in stub shafts which support the planet gears. At least one radial passageway in each stub shaft provides lubricating transmission fluid to a bearing assembly disposed between the stub shaft and the planet gear.