A transmission unit for a motor vehicle transmission includes a drive gear (6) which is arranged rotatably on an intermediate shaft (5) and which can be fixed to the intermediate shaft (5) for the transmission of drive power via clutch means. On one side flank (9) of the drive gear, a first gear portion (10) is provided which can be connected to a corresponding shaft-side second gear portion (11) via an internally toothed sliding sleeve (12). On the opposite side flank (13) of the drive gear, a parking lock gear portion (14) is provided for engaging a pawl (15) to block the transmission unit when the vehicle is at a standstill.