New heavy-duty Actros truck: The Mercedes-Benz among trucks
Its looks have been optimised in the wind tunnel, its technology and engineering are masterful and its cab is a unique combination of workplace and home from home: the new Mercedes-Benz Actros is the new benchmark for premium-class trucks. It reconciles high performance with low fuel consumption, its emissions are lower in pollutants than any comparable vehicle and its has undergone testing of unprecedented intensity. The Mercedes-Benz Actros has taken the motto for the Frankfurt International Motor Show – "The future begins today" – at its word.
Polished up and streamlined for fuel efficiency in the wind tunnel
A truck in the wind tunnel? All part of the development routine at Mercedes-Benz. The engineers subjected the Actros to 2600 hours of intensive testing and optimisation in the wind tunnel. In view of a frontal area of around 10 m2, consisting of a height of 4.0 m and a width of 2.5 m, and annual mileage in the order of 150,000, every detail of the cab and its attachments is crucial. The design of the air deflectors on the roof, the roof itself, the front apron, the corner panelling and the cab-side extenders have been evolved with a meticulous attention to detail. Perforated slats on the radiator grille, a temperature-controlled radiator shutter, door leaves extended downwards, side panelling between front and rear axle – all these aspects have undergone testing to make the new Actros the most economical truck on the road.
On the outside, the new Actros sports a striking and powerful, quintessentially Mercedes-Benz appearance, boldly displaying its star credentials. It takes up visual trends from the current passenger car range, adopting them into the world of commercial vehicles. In view of its long product lifecycle, the new Actros shuns short-lived, fashionable features, however. It embarks on its career with an optimistic and friendly smile on its face – the new Actros is powerful, but not aggressive in character.
A true dream cab: more spacious than ever
A workplace to be envied: the generously proportioned cab of the new Mercedes-Benz Actros sets new benchmarks in spaciousness and ergonomics, quality of materials and appointments. The superior standards begin with the new multifunction key: suspension level control, activation of the interior lighting, call-up of key operating data, level of the fuel tank and other fluids, tyre pressure monitoring, activation of auxiliary heating or stationary air conditioning – all these functions and more besides can be carried out at a distance of up to 100 m with this truly all-round key. Just for the record: the door also serves to lock and unlock the doors.
Typically for a truck, the cab on the new Actros is available in a range of different variants. Less typically, two widths and no less than six height and roof variants are available, tailored precisely to individual operational requirements. And anything but typically, the majority of cabs for the new Actros feature a flat floor, offering generous freedom of movement on board. Particularly impressive is the new Actros with GigaSpace cab and almost 12 cubic metres of space inside – a real dream workplace.
Cockpit and living area separated for the first time
Space and freedom of movement are of great importance in long-haul trucks. A driver may spend days or even weeks on the road in such vehicles. The cab thus serves as the driver's workplace, living area and sleeping berth in one. In view of this situation, the cockpit and living area have been separated from one another for the first time in the new Actros by means of the colour scheme and the cockpit's geometric design. The quality finish and feel of the interior appointments are on a par with the standard encountered in upper-range passenger cars – the new Actros is the Mercedes-Benz among trucks.
In keeping with the interior as a whole, the driver's seat has also been developed especially for the new Actros. It boasts a fascinating range of adjustment features: in addition to the customary basic functions, the air-sprung comfort seat also offers automatic weight adjustment, adjustable vertical dampers, lateral contour support, seat depth adjustment, shoulder support, horizontal springing and pneumatic lumbar support. The top-of-the-range variant even incorporates a massage function with pulsating air cushions in the backrest.
The driver receives tips on his style of driving
The cockpit of the new Actros is perfectly designed to meet the driver's needs. The multifunction steering wheel with its rim offering a good grip corresponds to the standard featuring in the current generation of passenger cars from Mercedes-Benz. The instruments offer more than the customary scope of information: the FleetBoard telematics system which comes as standard analyses the driver's style continuously by reference to numerous parameters. On the basis of the analysed data, the driver receives ongoing analyses and tips on his current driving style.
Numerous practical stowage facilities accommodate small and large items alike. Large stowage compartments provide an ideal base for a coffee machine or laptop. An integrated folding table is optionally available on the co-driver's side. The interior lighting adapts to the driver's needs: ceiling lamps ensure optimum illumination, with the work area lighting assisting the driver when studying documents, for example. The anti-dazzle green night lighting conjures up a pleasant atmosphere for night-time driving. The indirect blue ambience lighting employing fibre-optic cables to great effect helps the driver to relax during breaks.
The relaxation area in the new SoloStar Concept
The optional new SoloStar Concept takes the relaxation zone on board a truck to a new dimension. The central relaxation area is a rounded corner on the co-driver's side. Even tall drivers are able to stretch out their legs in this seating scenario and make themselves comfortable. A folding table provides an additional convenience factor. The beds in the new Actros offer even greater relaxation. They measure 2200 x 750 mm – more than enough even for the tallest drivers. Seven-zone cold-foam mattresses with an adjustable back section offer lying comfort on a par with that of a high-quality bed at home. The upper of the two beds can be levelled with a spirit level.
The heating utilising residual engine heat ensures a pleasant temperature during breaks or waiting times. During longer stops, the auxiliary heater goes into operation. The standard scope of equipment also includes air conditioning with automatic temperature control. A stationary air conditioning system is optionally available. This system stores cold which is generated while the vehicle is in motion, using it to cool the cab for up to eight hours at the end of the working day – a relief on hot summer nights, for example.
Plenty of space for luggage – and a shaving mirror
The stowage space in the new Actros boasts exceptional dimensions and accessibility. It is able to accommodate sufficient supplies and luggage even for long trips. With the Actros GigaSpace the stowage capacity totals 975 l – twice the luggage space available in a Mercedes-Benz C-Class. The outside flaps even open wide enough to stow away beverage crates.
Details transform the cab of the new Actros into a multifunctional home from home. The stowage compartment above the co-driver's area conceals a towel holder. A shaving mirror with flexible mounting is also on board. A spacious refrigerator box is optionally available. Similarly to the Mercedes-Benz passenger cars, various lines are available to upgrade the interior of the new Actros: the Home-Line emphasizes the new Actros's home-from-home character with wood-look trims and a door mirror in almond beige. This line also includes a leather steering wheel, with a wood/leather steering wheel available as an option. The Style-Line brings out the new Actros's dynamic character with chrome parts in brushed metal and interior door mirrors in black-silver velour. A chrome bar on the sunblind, chrome covers for the mirror housings and an illuminated Mercedes star lend the new Actros an extrovert character.
A real powerhouse: plenty of thrust right from the lowest revs
BlueEfficiency Power is the name of the game for the new engines in the new Mercedes-Benz Actros – combining clean running and power. The experience of driving with these engines is as impressive as these key data suggest: with a displacement of 12.9 l the six-cylinder in-line engines generate 310 kW (421 hp) and 375 kW (510 hp) in four stages, with maximum torque ranging between 2100 and 2500 Nm. The nominal engine speed stands at 180 rpm, with maximum torque available from 1100 rpm. These figures only provide a rough outline of the engines' performance, however: almost 100 percent of their full power output is already available at 1400 rpm, and high torque is on tap right from 800 to 900 rpm.
The engines are outstanding feats of engineering: two composite overhead camshafts with gear train and four valves per cylinder are just some of the distinguishing features. An outstanding attribute is the unique fuel injection technology based on a common rail system with pressure boost. A pressure of around 900 bar is generated in the rail. In the individual injectors, this pressure is boosted to as high as 2100 bar. Injection timing point, injection quantity, injection pressure and the pressure characteristic are all variable. Equally innovative is charging of the engines via an exhaust gas turbocharger with asymmetric turbine casing. This method provides for improved response.
The six-cylinder in-line engine has already demonstrated its extreme durability in extensive tests and in variants for other continents: the new engines achieve a mileage of at least 1.2 million km without overhauling. The maintenance intervals are equally spectacular, with up to 150,000 km possible between oil changes, depending on the vehicle's operating conditions.
Emission control: the exhaust muffler as a miniature chemical processing plant
The efficient emission control system marks a milestone in the development of clean automotive technologies. The new Actros already complies with the future Euro VI emissions standard, which will not become mandatory until 2014. Compliance with Euro VI requires more sophisticated technology: the new Actros combines SCR technology with AdBlue injection, exhaust gas recirculation and particulate filter – the exhaust muffler becomes a mini-chemical processing plant devoted to pollution control. The new Actros is optionally available in a variant corresponding to the current Euro V emissions standard.
Transmission: fast and precise gear-shifting
Transmissions are a fascinating aspect of truck technology and engineering. The new Actros is a high-tech trailblazer here with its PowerShift transmission. The fully automatic twelve-gear unit provides for fast gear-shifting with a precision which even the best driver cannot match. The transmission is operated by means of a steering column lever. The transmission supports the driver in diverse ways, with a choice of three driving programmes – Standard, Economy and Power – according to the demands of the given transport operations. A crawl function helps during manoeuvring much in the same way as with an automatic transmission, while a rocking mode is useful on slippery surfaces. EcoRoll mode switches the transmission to neutral when appropriate and subsequently engages the correct gear automatically, for maximum fuel economy in rolling phases.
Cruise along at only 1260 revs
Five different final drive ratios enable individualisation of the new Actros in accordance with its individual operational needs. This provides for a customised truck in line with the given body, weight and the topography of its typical routes. The high-torque engines allow high gearing: with the standard axle, the new Actros cruises along at only 1260 rpm at a motorway speed of 85 km/h – a prerequisite for low fuel consumption.
Air suspension as standard
The chassis and suspension play a major role on trucks as on passenger cars, though with a different emphasis. The new Actros comes with air suspension on the rear axle as standard, with additional front air suspension available as an option. The cab is additionally provided with a four-point suspension system, the top-of-the-range variant even featuring air suspension. Apart from the accuracy and precision of the speed-sensitive power steering, the variable power-assisted steering also saves fuel. The same applies to the auxiliary units operating in on-demand mode: from the alternator to the air compressor for the brake system, they all operate at zero fuel consumption in overrun mode.
In view of the permissible gross weight of 40 tons, the brakes play a particularly important role. The new Actros is fitted with internally ventilated disc brakes on all axles. A new feature is a particularly effective three-stage engine brake, which has a power output of up to 400 kW (544 hp) – more than the vehicle's engine. Even greater braking power is supplied by an auxiliary brake in the form of a retarder, whose brake power peaks at an outstanding 750 kW (1020 hp).
Assistance systems: a host of safety features on board
In the interests of maximum safety, diverse assistance systems are available for the new Actros. Proximity Control Assist maintains a preset safety distance, adapting the vehicle's speed accordingly. In addition, with the new stop-and-go function it now even controls moving off and stopping in congested traffic. Lane Keeping Assist warns the driver in good time if the truck threatens to leave its lane due to inattentiveness on his part. Stability Control Assist, which comes as standard, is the equivalent of ESP for trucks. Developing such a system posed a major challenge in view of the combination of tractor and semi-trailer and the large difference of around 25 tons between kerb weight and permissible gross weight. As a unique feature, Active Brake Assist initiates emergency braking automatically in the event of danger.
Sometimes it is the minor details that make the difference. The fifth wheel coupling with sensor technology informs the driver of its locking mechanism's status via a display in the cab. The exterior mirror with manoeuvring function widens the field of vision by ten degrees by means of automatic adjustment when reverse gear is engaged.
Record low fuel consumption demonstrated in 10,000 km trial
Maximum economic efficiency is a prime consideration when developing commercial vehicles. Economy is tantamount to environmental friendliness here, as every litre of fuel saved not only lowers costs but also reduces emissions and helps to preserve finite resources. Despite the sophisticated emission control technology, a key priority for the new Actros was thus nevertheless a further reduction in fuel consumption. In an extensive road trial, the new Actros has demonstrated how its designers have indeed achieved a feat tantamount to squaring the circle.
Laden to a weight of 40 tons, two new Actros 1845s complying with emissions standard Euro V and Euro VI each covered the 10,000 stretch on the typical east-west route from Rotterdam to Szczecin and back. An Actros 1844 from the preceding model series also completed the trip for the purposes of comparison. The fuel consumption test was carried out under the supervision of the authorised Dekra inspection agency, ruling out any underhand practices. Numerous assemblies and tanks were lead-sealed and all refuelling operations were monitored.
Even the experts were astounded at the results. The established fuel-efficient Actros 1844 clocked up fuel consumption of 27.1 litres per 100 km as a reference value. The new Actros 1845 BlueTec 6 complying with the Euro VI emission standard – which will not become mandatory until 2014 – completed the trip on 25.9 litres per 100 km, thus undercutting its predecessor by 4.5%. The new Actros BlueTec 5 complying with the Euro V emissions standard shows a fuel consumption level of just 25.1 litres per 100 km – 7.6% below the reference value. This figure corresponds to fuel consumption approaching only 1 litre to 100 km per ton of payload for the new Actros. Even fuel-efficient passenger cars fall short of this fascinatingly low value, which was attained with standard production heavy-duty trucks in daily operating conditions.
The most thoroughly tested truck ever
The new Actros has been developed according to the strict rules of Daimler Trucks' eleven "quality gates", which control the development process in defined steps. This process entails countless individual tests on engines, transmissions, other drive components, chassis and cab on test benches, as well as tests on rough roads, endurance tests, functional tests and tests in a climatic chamber. All this is no substitute for the acid tests faced by the complete vehicle in real road trials, however. The new Actros has covered 20 million kilometres on the road, including daily use in intensive trials conducted by customers.
The diverse tests are rounded off by two unforgiving trial phases. For 20 years now, Mercedes-Benz has been testing its trucks in the searing heat of the Sierra Nevada in southern Spain. The route winds its way up the 45 km from Granada to the winter sports venue of Solynieve, negotiating inclines of between 8% and 12% along the way. Outside temperatures in excess of 40 degrees Celsius apply at the start of the route. This is an ordeal not only for the vehicle, but for the test drivers, too – with air conditioning ruled out in the interests of comparability. An acid test takes place after completing just over half of the climb: three stops, each followed by a three-minute rest before briefly moving off again. Due to the lack of cooling from the airstream, this results in an extremely hot engine. The heat resistance of exhaust systems, the cab's equipment and appointments, the electronics, steering, brakes and tyres is measured.
Winter tests at the Arctic circle subjected the new Actros to extreme conditions at the other end of the spectrum. For many years now, Daimler AG has been running a test camp for trucks here in the Finnish town of Rovaniemi. The test programme here focuses on the engine's cold-starting properties, its temperature characteristic, cold start noise and the behaviour of the entire drive train, including transmission and gear-changing, at extremely low temperatures. Other key test items include heating of the cab, the icing and de-icing of windows, doors and exterior mirrors, the misting-up of headlamps and soiling.
The new Mercedes-Benz Actros passed these extreme tests. While the production vehicles will never encounter such harsh conditions in daily operation, it is reassuring to know that the new Actros would be able to cope in these scenarios.
Source: Daimler AG
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