The Mercedes-Benz Actros is a heavy duty truck introduced by Mercedes-Benz in 1995. It is normally used for long-distance haulage, heavy duty distribution haulage and construction haulage. It is available in weights starting at 18 tonnes and is powered by a V6 or V8 cylinder diesel engine with turbocharger and intercooler. Daimler Trucks/Lorries launched the version II of the Actros in 2002, and the version III in 2007
The Mercedes Benz Actros is equipped with two types of engines. The OM 501 LA-541 and the OM 502 LA-542. The OM 501 is a 12-litre V6, and has outputs ranging from 310 HP to 460 HP. The engine management system employed by this engine is the PLD (Pumpe Leitung Duese-German abbr) which incorporates single plug-in pumps for each cylinder supplying fuel under pressure (up to 1,600 bar) to the injection valves. A control unit MR monitors all engine operating conditions via several sensors and varies the injection pressure to suit each operating condition.
The fourth version offers several engine options in either Euro-5 or Euro-6 compliant models, with various power output.
The second Actros generation comes with an electronic sequential gearbox that Mercedes-Benz has dubbed the “Telligent Gearbox”. It pushes forward the principle used in some earlier Mercedes-Benz tractors; using the gearshift lever to command a pneumatically actuated system that changes the gears. The Telligent gearbox utilizes a computer, together with a load-sensing system on the fifth-wheel coupling, to estimate the proper gear that the truck must be in. For example, if you want to upshift, the computer estimates the load on the tractor and the current engine mode, and gives you the proper gear for decreasing engine RPM. On the other hand, if you want to downshift, the computer assumes you wish to overtake, and gives you a proper gear for acceleration.
There’s an automatic version which works like the Tiptronic system found in Mercedes-Benz cars.
The fourth-version launched in 2011 offers exclusively the 12-speed powershift transmission.
The system consists of a small lever mounted under the right armrest and a flat switch underneath. The lever is slightly tilted, so that it matches the natural curve of the driver’s hand when it’s on the armrest. The lever has two buttons on either side. When at a standstill, the driver must push the left button, then (while holding it), push the lever forward and release it select fourth fast. The current gear is shown as a large number on the main display. After doing this, the driver steps on the clutch pedal and waits for approximately two seconds. After the gearshift has completed, a double click is sounded through the speakers, and the driver proceeds with pulling off as normal.
Once moving, the driver has two choices. He or she may push or pull the lever to let the computer choose the gear for them, or they can use the splitter switch (the small switch under the lever) to pre-select gears. Either way, the gear is selected first, then the clutch is depressed. For example, if you’re in fourth fast, pulling the splitter switch up once pre-selects fifth slow.
The right button (known as the ‘flush button’, as it is flush with the lever) is used to switch to neutral.