Abstract:The powder metallurgy (PM) automobile synchronizer gear hub is starting the trend of replacing steel hub for it can meet the requirements of energy conservation, environmental protection and sustainable development. With the rapid development of automobile industry and the continuous increase proportion of powder metallurgy parts in automobile parts, the PM synchronizer gear hub has more and more market demand, where the synchronizer gear hub gradually transforms from 5 MT to 6 MT, from MT to AMT and DCT. The change of product structure and the higher and higher requirements of technology lead to some technical difficulties in the practical manufacturing, which have restricted the improvement of its quality and producing efficiency. The solutions were proposed to solve the technical difficulties in the practical manufacturing.