A drive assembly for vehicles with front wheels and rear wheels,
especially for tractors, agricultural machinery, construction machinery
or for self-driving machines, has an engine (1), a first drive (15) to
drive the rear wheels, a second drive (27) to drive the front wheels, an
adjustable hydraulic pump (5) driven by the engine (1), and an adjustable
first hydraulic motor (9). The first hydraulic motor (9), with respect to
drive, is connected to the first drive (15) to drive the rear wheels.
Also, the first hydraulic motor, with respect to drive, may be connected
to the second drive (27), to drive the front wheels. A second hydraulic
motor (10), with respect to drive, can be connected to the second drive
(27) to drive the front wheels. The first hydraulic motor (9) has a high
coefficient of efficiency within a first driving speed range of the
vehicle. The second hydraulic motor (10) has a high coefficient of
efficiency within a second driving speed range of the vehicle. The first
driving speed range is above the second driving speed range, with both
driving speed ranges overlapping.