The invention relates to a transmission drive unit (10), comprising a transmission element (11) that is rotatably arranged on the drive side in a transmission housing (15), with which transmission element a driving torque can be transmitted to at least one guiding element (25, 26) of a coupling element (20) on the output side, and a load torque lock, with which a torque introduced by the output-side coupling element (20) via the at least one guiding element (25, 26) can be locked, wherein the load torque lock comprises a locking element (42) that is preferably designed as wrap spring that cooperates with a brake element (34; 34a; 34b), which comprises a friction surface (51) and is arranged non-rotatably in the transmission housing (15), for locking the torque. According to the invention, the brake element (34; 34a; 34b) consists of a plurality of sheet metal elements (48, 49; 57, 58; 57b; 58b) and the sheet metal elements (48, 49; 57, 58; 57b; 58b) are connected to each other.