An axle drive block for a motor vehicle, comprising a first and a second differential in a driven housing. Both of the differentials are coaxially aligned planetary spur gears, the sun wheels of which are drivably connected to the semiaxes of the first driven axle. The planet wheels of both differentials mesh the joint ring gear of the sun wheels. In order to lock the interaxle differential, the housing is provided with a first striking surface interacting with a second striking surface which is pressed thereto by ball ramps.