T-series Automobile transmission is suitable for medium and large bus and truck, applying three-shaft fixed-shaft transmission, rotary shaft-pulling plate-fork shifting mechanism, lock-ring synchronizer to shift, optional single-lever or sorts of flexible shafts mechanism, thus easy and reliable in shifting. It can be installed left or right horizontally or vertically, being different varieties to increase adaptability in vehicle. It is designed as ground gears, constant engaged helical gears; smooth in transmission. The series product is mature in technology and high in reliability.