Method for controlling gear changes in a transmission of a motor vehicle drivetrain

A method for controlling gearshifts in a transmission (4) of a motor vehicle drivetrain (1), wherein a shifting strategy is based at least in part on operation of a sustained-action braking device (10), the method comprising:

• initiating actuation of the sustained-action braking device;
• determining, after initiating use of the sustained-action braking device, a starting criterion for initiating actuation of the sustained-action braking device (10);
• and
• executing, based on the starting criterion, an operation selected from (i) comparing a current workload (xAusl_Ret) of the sustained-action braking device (10) with an associated threshold value (xGrenz1, xGrenz2), and (ii) shifting a gear directly to a lowest possible gear of the motor vehicle transmission (4).

A transmission control unit (5) configured to take into account operation of a sustained-action braking device (10) when devising a shifting strategy for gearshifts in a transmission (4) of a motor vehicle, the control unit configured to:

• (i) initiate actuation of a sustained-action braking device;
• (ii) determine, after initiating actuation of the sustained-action braking device, a criterion for initiating actuation of the sustained-action braking device (10);
• (iii) execute, based on the starting criterion, an operation selected from (i) comparing a current workload (xAusl_Ret) of the sustained-action braking device (10) with an associated threshold value (xGrenz1, xGrenz2), and (ii) shifting a gear directly to a lowest possible gear of the motor vehicle transmission (4);
• and
• (iv) adapt the shifting strategy if the current workload (xAusl_Ret) of the sustained-action braking device (10) exceeds the threshold value (xGrenz1, xGrenz2).