General Hydraulic Auxiliary Drive (HAD) For the first time the Hydraulic Auxiliary Drive (HAD) for the front axle is available for models 963 and 964. In this system the front axle is fitted with hydrauli- cally powered wheel hub motors which are supplied by a high-pressure pump mounted on the rear of the engine. The HAD is a starting-off aid, not a continuous drive system. Depending on the drivetrain configuration, the HAD can be used in the first 5 gears up to a speed of approx. 30 km/h. It should be noted, however, that the system is designed for a total operating time of 5% of the vehicle's mileage.
The HAD is a torque-controlled system that sets the optimum drive torque at the front axle according to the driving situation. To do this, the system estab- lishes whether a torque is necessary at the front axle, and regulates the distribution of torque between the front and rear axles automatically and independently of the driver. Compared to a conven- tionally powered all-wheel drive vehicle with transfer case, the HAD provides a weight advantage of up to 340 kg and can also be used with a EURO trailer.
Together with the automated manual transmission (including those with secondary water retarder and the transmission power take-offs NA 121, NA 123 and NA 131), traction can be achieved on slippery ground without interrupting the powertrain. The HAD is available for the following vehicles: Model 963 4x2 with engine 471 (late 2014) Model 964 4x2 with engine 471 (early 2015) Model 963/964 6x2/6x4 with engine 470/471 (mid-2014) 44 i Introduction of the New Truck Generation - The New Arocs (Model 964) – This printout will not be recorded by the update service. Status: 01 / 2013 –