Abstract: A transmission between a drive aggregate and a drive output of a vehicle drivetrain has a hydrodynamic starting element and a powershiftable main transmission with a plurality of forward gears, at least one reversing gear, a transmission input, a transmission output, and frictional shifting elements. In each gear a first number of shifting elements are closed and a second number of shifting elements are open. A downstream range group has at least one interlocking shifting element which can be shifted between a first and second driving ranges. With the drive aggregate running, the vehicle at a standstill or nearly so, the main transmission in neutral, and a shift request received to change the downstream range group, shifting elements of the main transmission are actuated, thereby bracing the transmission input against a transmission housing and decoupling the transmission input from the transmission output. The downstream range group is then shifted.