Feet firmly on the ground: Actros with starting-off aid HAD
Vehicle & technology
Eduard Illmaier is transporting logs. He does this both on motorways and on forest tracks. The Hydraulic Auxiliary Drive (HAD) starting-off aid offers him additional traction when needed.
Things are about to get bumpy. It has taken Eduard Illmaier 20 minutes with his Actros on the number 20 rural road. He has nearly reached his first destination for today, a timber yard on the border between Styria and Lower Austria. Access to the loading area, where he will load his semitrailer with 30 cubic metres of timber, is unsurfaced, slippery and steep. "Watch out!", says Eduard. On the instrument panel he activates the engageable starting-off aid Hydraulic Auxiliary Drive (HAD) and presses the accelerator pedal. The HAD symbol in the display lights up blue – a sign that the system's hydraulic wheel hub motors are bringing an additional output of up to 40 kW per wheel to the front axle of the Actros. In combination with the Mercedes PowerShift 3 automatic gearshift HAD facilitates sufficient traction on this terrain, too, and even on muddy and steep forest or access tracks. "I always switch it on when the drive axle is threatening to lose its grip", says Eduard. Sounds like all-wheel drive, but it's not. Instead, HAD combines the advantages of an all-wheel drive with a classic drive system. Compared with permanent all-wheel drive the system is 500 kilograms lighter, 350 kilograms compared with the engageable one. There is also no mechanical link to the front axle. This means that HAD is very good at clocking up bonus points when it comes to consumption, too.