Gear drive unit, particularly for a seat adjustment or a power steering system, with at least a support element

The invention relates to a transmission drive unit (10), in particular for seat adjustment or power steering, with a transmission housing (15) and an output gear (28) arranged in a rotationally fixed manner on an output shaft (42) projecting therefrom, wherein the output shaft (42) is directly, at least partially enclosed by a support element (38), against which the output gear (28) is supported upon axial force application from outside.