Abstract: A mobile vehicle comprising a shiftable transmission with fixed gear ratio steps and a controllable friction clutch contains a distance sensor, which is connected to an inch pedal and in which the starting position and the end position of the inch pedal are adjusted by an electronic control unit and allocated to an inch effect from 0% to 100%. Due to the electronic adjusting process of the inch pedal path via the inch effect and the service brake, the intersecting time between the service brake and the actuating force of the clutch can be adjusted. The driving comfort of the vehicle is increased and the risk of damage to the multi-disk clutch is reduced.

Abstract: The invention is based on a process for determination of a coefficient of friction (&mgr;) of a hydraulically activated coupling (4, 5, 6) or brake (7, 8, 9) in a load-shifting transmission (1). It is proposed that a drive shaft (14) of the transmission (1) be driven with a specified torque (T), that an output shaft (15) of the transmission (1) is blocked with a closed coupling (4, 5, 6) or brake (7, 8, 9) during a calibration run, the activation pressure (p) of coupling (4, 5, 6) or brake (7, 8, 9) is reduced in accordance with a specified course over time, the differential rotational speed (&Dgr;n) between the input (17, 18, 19) and the output (20) of the coupling (4, 5, 6) or brake (7, 8, 9) is recorded, the activation pressure (p) is ascertained in which the differential rotation speed (&Dgr;n) is greater than zero and a separation coefficient of friction (&mgr;separation) is computed on the basis of torque (T), activation pressure (p) and a construction-conditioned coupling constant.