The invention relates to a drive unit, notably for a lift truck, in which a spur gear system (2) is driven by a motor and the driven gear (3) of the spur gear system (2) is connected to a planetary gear train which drives the driving gear of the vehicle. Between the planetary gear train and the spur gear system (2) a multi-disc brake is positioned which is able to connected the driven gear (3) with a crankcase part (9) in a non-positive fit. In the non-pressurized state the multi-disc brake (6) is closed by means of springs (17). By applying a hydraulic pressure in a first hydraulic cylinder (14) the parking brake is released and by applying a hydraulic pressure to a second piston (16) the service brakes are actuated by the fact that the second piston (16), which is arranged inside the piston (15) of the first hydraulic cylinder (14), is displaced axially and applies the multi-disc brake (6).