The new Mercedes-Benz Actros is the very first truck to receive the newly-premiered Blue Efficiency Power units that fully comply with the stringent Euro VI emission standard. These diesel engines boast excellent technical characteristics, low fuel consumption, exemplary robustness and longevity and provide high levels of output and torque across a wide range of rpm. Engineers have also mastered the X-PULSE, a new commonrail system with pressure booster, and a powerful and dynamic three-stage engine brake. Furthermore, the new powerplants feature efficient emission control solutions: the SCR technology, exhaust gas recirculation and the particulate filter. Power is sent to wheels thanks to the introduction of the third generation of Mercedes-Benz PowerShift fully-automated transmissions, tweaked for faster and more effective gear shifts.
The launch of the new Mercedes-Benz Actros heralds the arrival of a completely redesigned range of heavy-duty engines which set new standards in many respects. The new Mercedes-Benz BlueEfficiency Power engine generation has been developed specifically for use in Europe and, from the outset, will meet Euro VI requirements. The first member of the new engine family to be in the spotlight is the Mercedes-Benz OM 471 six-cylinder in-line unit, with an output range that covers the bulk of European long-distance-transport requirements. The OM 471 counters the unavoidable extra expense for Euro VI by incorporating state-of-the-art technology. As a result, the new Actros is not only cleaner, it also consumes far less diesel than its predecessor.
New engine already meets the requirements of the forthcoming Euro VI emissions standard
With this new engine generation, Mercedes-Benz continues its tradition as a trailblazer in terms of environmental compatibility. The OM 471 is the first engine in its class to be homologated in accordance with the future Euro VI emissions standard, so marking the start of a new era a full two years before Euro VI actually becomes law. Euro VI brings further significant reductions in, above all, nitrogen oxides and particulates in the exhaust gas.
The new Mercedes-Benz OM 471 covers an output range of 310 kW (421 hp) to 375 kW (510 hp), with peak torques between 2100 and 2500 Nm. During development of the OM 471, the Mercedes-Benz engineers were able to call upon a wealth of experience: the core design of the engine is based on the new platform used for Daimler Trucks' heavy-duty engines. These have been used very successfully since 2007 in trucks produced by Daimler's North American Freightliner brand (built by company-owned engine manufacturer Detroit Diesel) and since last year by Fuso in Japan.
BlueEfficiency Power: top class from Mercedes-Benz
Operators as well as drivers of the new Actros want powerful engines with good traction and low fuel consumption, along with high overall economic efficiency. They expect the best possible performance as well as refined, quiet running and exhaust gases that are low in pollutants. The new engine generation meets these requirements thanks to its robust construction and high-grade engineering, including four valves per cylinder, two overhead camshafts and a fully electronically controlled injection system with pressure booster that is unique in the world.
Like the Actros itself, the new Mercedes-Benz engines are top class in every respect. Top class in terms of the outstanding and innovative engine technology with exceptional economy and refinement thanks to the new, unique X-PULSE injection system. Top class in terms of excellent engine dynamics thanks to turbocharger technology. Top class in terms of low emissions thanks to the combination of SCR technology, exhaust gas recirculation and a particulate filter. And top class in terms of the powerful, new engine brake. Not to mention the new engines' serviceability and durability.
A wealth of output and torque variants
The Mercedes-Benz OM 471 is available with a choice of four outputs and torques for the new Actros. These configurations are suitable for typical European application conditions and meet operators' and drivers' requirements. The following versions of the Mercedes-Benz OM 471 are available for the new Actros:
Output (kW) - Output (hp) - Torque (Nm)
310 - 421 - 2100
330 - 449 - 2200
350 - 476 - 2300
375 - 510 - 2500
One of the particular highlights of the new OM 471 is the fact that, if the standard rear-axle ratio of 2.611 is specified, 200 Nm of extra torque are provided when the automated transmission is in top gear so as to prevent downshifts when driving uphill.
BlueEfficiency Power: high torque even below 1000 rpm
The rated engine speed of the new engines is set at 1800 rpm for all output variants, with the maximum torque available at just 1100 rpm. But these figures can only be a guide: as a result of the very steep output curve immediately before the main operating range, most of this maximum torque is already available at an engine speed of just 1000 rpm. Even below 1000 rpm, the torque is surprisingly high. This results in an extension of the usable engine speed range at the bottom end – down to around 800 to 900 rpm, depending on the route profile – with a correspondingly positive effect on fuel consumption.
Excellent driveability: high output across a wide rpm range
The same is true of the output curve: even at 1400 rpm, the engines deliver almost 100 percent of their full output. In reality, on the road, the output and torque curves combine to ensure excellent driveability with a high output in all key engine speed ranges. The Mercedes-Benz OM 471 reinforces this sense of dynamism with its quiet, smooth running, which is nevertheless characterised by the brand's hallmark sonorous and distinctive sound.
Compact six-cylinder in-line engine
The design of the new Mercedes-Benz OM 471 is based on six cylinders mounted vertically in-line – a platform that bodes well for the smooth running of the engine. The long-stroke design of the Mercedes-Benz OM 471, which has a bore of 132 mm and stroke of 156 mm, gives it excellent pulling power. The engine is categorised in the heavy-duty class for heavy-duty commercial vehicles. The dry weight of the Euro VI version is 1146 kg, while the weight to DIN 70020-A is 1126 kg.
Exemplary robustness and longevity
In order to meet the demands made of the new Actros class of high-powered heavy-duty trucks, exceptional robustness and durability are among the outstanding characteristics of the engine. The crankcase, for example, is made of a grey-cast-iron material developed and patented specifically for this engine generation and includes vertical structures and ribbing to make it very rigid. This design also reduces noise emissions.
The single-piece pistons, made from steel to maximise their service life, each feature two compression rings, an oil control ring and splash-oil cooling. A protective coating ensures that the engine will perform under load, even while it is being run-in. The almost negligible distortion of the pistons and the rigid crankcase keep oil consumption and blow-by losses to a minimum – so reducing costs and improving environmental acceptability. The fine plateau honing of the cylinder liners likewise reduces oil consumption as well as friction losses.
Optimum engine cooling is ensured by wet cylinder liners. The main cooling flow circulates around the upper third of the liner, while a secondary flow cools the lower section, which is not subject to such high temperatures. In general, the distances travelled by the coolant are kept short, making the cooling process here very efficient. The cooling thermostat is located at the intake end to ensure precise control. Larger radiators with a higher output reduce the thermal load whilst the fan does not have to operate as frequently, thus reducing fuel consumption.
Smooth running and an extremely rigid design
The "cracked" connecting rods are split at the connecting rod eye. In this process, the connecting rods are broken at a defined point, producing an extremely robust, close-fitting join with a large surface area when they are screwed back together. A precisely balanced seven-bearing crankshaft ensures exceptionally smooth running of the engine.
The highly rigid crankcase, steel pistons, and reinforced connecting rods and bearings were selected with the high engine ignition pressures in mind. To maximise efficiency, these have been increased from their previous level of 180 bar to over 200 bar.
The turbocharger, starter motor and crankcase ventilation system are all located on the hot side of the engine, while the engine control unit, the oil coolant module with filter and coolant pump, the fuel pumps for the high- and low-pressure system, and the consumption-optimised two-cylinder air compressor with on-demand control are grouped together on the cold side of the engine for ease of maintenance.
Exceptionally robust cast-iron cylinder head
The one-piece cylinder head for the new engine is made of grey cast iron with vermicular graphite (also known as CGI). It is exceptionally robust and designed for the high ignition pressures in the new engines.
Efficient gear drive, double overhead camshafts
At the front end of the engine, poly-V-belts drive the alternator, the coolant pump, the refrigerant compressor and the fan. The now closed-loop coolant pump is only activated as and when needed so as to reduce fuel consumption.
The extremely compact and rigid gear drive is located at the engine's output end, where it operates exceptionally efficiently, quietly and smoothly. Each of the camshafts controls two intake and exhaust valves arranged vertically in the cylinder head via low-friction rocker arms mounted in friction bearings. Rather than being milled from a solid piece of material, the camshafts are of "composite" or "assembled" design – a premiere for engines of this size – and are based on a hollow construction to save weight. They are mounted in a die-cast aluminium camshaft frame with seven bearings.
X-PULSE: unique common-rail system with pressure booster
One of the key aspects of the new engine generation for the new Actros is clean and efficient fuel combustion based on a flexible, fully electronically controlled common-rail system. Flexible in this case means that not only can the injection pressure, timing and quantity of fuel injected be varied, but also the injection rate, thanks to the new X-PULSE injection system with pressure booster that has been developed exclusively with Daimler Trucks.
Maximum injection pressure of 2100 bar
In the X-PULSE common-rail system with pressure booster, the twin-piston high-pressure pump produces a maximum pressure of around 900 bar in the common rail. This pressure is then boosted to up to 2100 bar in the individual injectors. The X-PULSE pressure booster can be varied on the engine map and adjusts continuously to the current engine operating conditions – for example to the demand for torque from the accelerator pedal. The engine control unit manages the injection point, injection quantity, injection rate, number of injections and injection pressure separately for each injector, enabling it to even out any differences between the various cylinders.
Pilot, main and post injections
X-PULSE allows an exceptionally high maximum injection pressure to be achieved as well as enabling free adjustment of the pressure and pressure distribution during main injection by means of two solenoid valves. As all the parameters are variable, each individual injection can be precisely adjusted to the specific situation.
Smooth running, economical, clean: main injection rate can be freely shaped
Many different forms of injection are possible with the new X-PULSE injection system. Their use depends on various parameters, such as the engine load: injection without pressure boosting but with just the pressure in the rail, injection with very early pressure boosting ("square" injection rate) or injection with late pressure boosting ("boot" rate). A variant in between ("ramp" rate) is also possible.
All in all, this means that for the first time it is possible to control fully the injection sequence at each engine operating point. As the highest pressure is only produced actually inside the injectors, the injections are exceptionally stable. In the case of the new Mercedes‑Benz engine generation, this results in quiet and smooth running with a high level of refinement, extremely low fuel consumption and minimal exhaust emissions.
Swirl-free turbulence, efficient combustion
The injection process takes place in a geometrically optimised combustion chamber with a shallow piston recess. The X-PULSE injector is positioned vertically and centrally between the vertically arranged intake and exhaust valves. It features an injection nozzle with seven injection orifices designed as miniature blind-orifice nozzles. The high maximum injection pressure and extremely fine fuel atomisation in the combustion chamber are the keys to efficient combustion. The combustion chamber is shaped to prevent swirl and tumble and to make the combustion of the fuel/air mixture as efficient as possible. The engines' relatively high compression ratio of 17:1 is also aimed at maximising economy.
Asymmetric exhaust gas turbocharger
The new Mercedes-Benz OM 471 has a turbocharger with an asymmetric turbine housing and fixed geometry as well as an intercooler. The asymmetric flow is an advantage, as the exhaust gases from the first three cylinders go directly through the exhaust gas recirculation system to the turbine without any losses. This process improves engine response.
Powerful and dynamic three-stage engine brake
Superb efficiency is one of the key characteristics of the new Mercedes-Benz OM 471, and this is also true of the engine brake. Mercedes-Benz uses a turbocharged decompression brake, which operates extremely effectively and quietly. The fast response time of less than 150 milliseconds is also remarkable.
The engine brake is controlled in three stages through the steering column stalk. In the first stage, the engine brake is activated on three of the cylinders. The remaining three cylinders are then activated in a second stage. In the third and highest stage, the EGR valve and wastegate are activated to increase the engine's charging level and so achieve the maximum brake power of 2300 rpm at 400 kW (544 hp). In addition to this manual actuation, the engine brake is also used in cruise control mode.
Motor control module MCM: everything under control
As the engine's "brain", the MCM (motor control module) is not only responsible for translating the demand for power governed by the driver's foot on the accelerator, but also for controlling and monitoring all the engine functions, from the start and rate of injection through to actuation of the engine brake.
By way of example: in order to achieve perfect synchronisation during gear changes, the engine needs to reach the requisite nominal speed as quickly as possible. To do so, it is even possible to fire individual cylinders whilst other cylinders are being decelerated by the engine brake. Very fast and smooth gear changes are therefore possible.
The control module uses sensors to constantly check factors such as oil level, the position of crankshaft and camshafts, the pressure in the common-rail system and the injectors, the turbocharger turbine speed, the temperature of the engine oil, coolant, fuel and charge air, the charge pressure, and the exhaust gas recirculation rate. As a result of this extensive monitoring, the engine always operates in its optimum range – the prerequisite for good performance, low fuel consumption, a long service life and low exhaust gas emissions.
Efficient emission control: SCR technology, exhaust gas recirculation, particulate filter
Conscious of the stringent requirements imposed by the Euro VI emissions standard, Mercedes-Benz has developed a combination of SCR technology with AdBlue insertion, cooled exhaust gas recirculation (EGR) and a particulate filter for the new BlueEfficiency Power engine generation in the new Actros. This solution has already proved successful on the road in commercial vehicles from Daimler Trucks on other continents. However, the configuration here is adapted specifically to comply with European emissions legislation, while the particulate filter, including its regeneration strategy, is also a special European development. All of the systems combine to ensure extremely efficient emission control.
The differences between the optionally available Euro V versions and the standard Euro VI variant include the omission of the particulate filter, a reduced recirculation rate in the EGR system and a smaller EGR cooler. To meet customer demand, there are also EEV variants in the line-up. These are based on the Euro V version. EEV and Euro V versions are available with a choice of three power outputs: 310 kW (421 hp), 330 kW (449 hp) or 375 kW (510 hp).
Low fuel consumption despite Euro VI: a milestone in engine development
Along with a high level of environmental compatibility, one of the key aims during the development of the new engine generation was to minimise lifecycle costs. First of all, this involves low fuel consumption. Despite the added complexity that was necessary to meet the requirements of the Euro VI emissions standard, these versions of the Mercedes-Benz OM 471 boast exceptionally low fuel consumption and achieve record figures in all versions of the new Actros. AdBlue consumption is also reduced drastically in the Euro VI versions.
The Euro V version of the OM 471 has even lower fuel consumption. It has a lower exhaust gas recirculation rate and dispenses with the particulate filter.
Exceptionally long service intervals ensure low lifecycle costs
At the same time, the developers have been concentrating on keeping maintenance costs down. The service intervals have now been extended to up to 150,000 kilometres, the precise figure depending on the vehicle type and its usage profile. This interval is an exceptionally good figure for an engine with exhaust gas recirculation. In reality, this means the new Actros models in many long-distance transport fleets will require just one annual maintenance call with an engine oil change. The generally maintenance-free particulate filter in the new Euro VI Actros only needs to be changed after 450,000 km and subsequently cleaned after every 300,000 km. The service interval for the air filter in the new Actros is likewise 300,000 km.
The excellent serviceability of the new engine generation also helps to reduce operating costs. A filter module fitted to the cold side of the engine includes the oil filter as well as the filter module for the fuel supply, itself comprising prefilter, main filter and the water separator for the fuel system, grouped closely together in an easily accessible position. The oil refill point is also accessibly located on the cylinder head cover – although the low oil consumption of these engines means that, in reality, the oil will only rarely need refilling.
Mercedes PowerShift fully-automated transmission
In all versions of the new Actros, the power is sent to the wheels through a Mercedes-Benz PowerShift G211 or G281 fully-automated transmission. These transmissions have already proven successful in the predecessor models. And they now offer even faster and more precise response thanks to their highly sensitive shift sensors. The ratios of the twelve-speed transmissions have been optimised for the new engines, the direct ratio in top gear serving as a basis for highly economical long-distance driving. As was the case with the predecessor, application-oriented extra functions such as EcoRoll mode, rocking mode and power mode make the driver's job easier.
New functions for transmission individualisation
New features include a crawler function in place of the previous manoeuvring mode. As in a passenger car with an automatic transmission, the clutch closes when the brake pedal is released. So the new Actros can now be driven at walking pace with a gear engaged but without the need to press the accelerator – making the driver's job even easier when stuck in traffic or when manoeuvring.
Likewise new is the range of freely selectable application-oriented drive programs. The Economy Drive package, installed as standard, offers the driver the already economical Standard drive program as well as an Economy program for significantly reducing fuel consumption on the road. The Economy program does not use kickdown, while the EcoRoll function cannot be deactivated, and the top speed is limited to 85 km/h. The optional Power Drive package includes the fuel-saving Standard program as well as a Power shift program which offers the driver optimum performance. Furthermore, this program allows a GCW of up to 120 t in heavy-duty applications. These individualised shift programs mean that the Actros can be ideally adapted to the particular application conditions.
Faster gear change, controlled by the steering column stalk
Another factor behind the top performance achieved by the new Actros is even faster gear changes with less loss of road speed, which has a positive effect on both average road speed and fuel consumption.
The transmission controls are also new: as every new Actros is supplied with a fully-automated transmission, a steering column stalk is now provided – for the rare occasions on which the driver has to intervene manually.
Tried-and-tested axles, longer ratios
The new Actros is available exclusively with fuel-saving hypoid axles. Although the tried-and-tested HL6 axle from the predecessor has been retained, it now has a new hypoid gear to reduce friction losses. This improvement in efficiency is reflected in lower fuel consumption.
The new high-torque engines with a far wider usable speed range and the "Top-Torque" torque increase in top gear combined with the optimised Mercedes PowerShift with shorter shift times allow a longer rear axle ratio to be used. The standard ratio for semitrailer tractors is now i=2.611 rather than i= 2.846 with a correspondingly lower engine speed level. At a speed of 85 km/h in twelfth gear, the engine in the new Actros runs at just 1260 rpm rather than 1370 rpm – another factor behind the lower fuel consumption achieved by the new Actros.
Furthermore, Mercedes-Benz has extended the range of available rear axle ratios once more. There are now five versions of the HL6 rear axle available for semitrailer tractors with a standard frame height and 315/70 R 22.5 tyres, ranging from i=2.533 to i=3.077. There are also five versions available for lowliner versions with 295/55 R 22.5 tyres, ranging from i=2.2278 to i=2.733.
Economy Packs: economical miracles in package form
If a fleet's main priority is maximum economy, Mercedes-Benz makes it easier to select the right components by offering ready-made Economy Packs at attractive prices. The Classic Economy Pack includes a tyre pressure monitoring system, wind deflectors and side panelling, while the Top Economy Pack also includes a retarder.
FleetBoard and service contracts further boost cost-effectiveness
It's not just the vehicle technology in the new Actros that boosts cost-effectiveness, telematic systems do their bit, too: FleetBoard is included as standard for the first time. The FleetBoard vehicle computer is fitted as standard on board every new Actros. The extensive FleetBoard services can be used free of charge for the first four months. Only after this period does a fee become payable, should the customer decide to continue using FleetBoard. FleetBoard services include trip recording, driving analysis, telediagnosis and maintenance management. What's more, the driver – and only the driver – receives short-time analyses of his or her driving style from the trip computer on the instrument panel display as part of FleetBoard EcoSupport. FleetBoard makes it possible to cut costs by five to 15 percent.
Customised service contracts likewise help to boost the cost-effectiveness of the new Actros. Given the longer service intervals, these are notably less expensive.
Source: Daimler AG
Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.
OFFICIAL PRESS RELEASE
Stuttgart/Mannheim, Germany, May 20, 2011
The Mercedes-Benz Citaro is the most successful urban regular-service bus of all time. Since series production first started in 1998, over 31,000 have been built. In that time, it has acquired international renown, having entered service in almost all major European cities and far beyond. First unveiled at the UITP Congress in Stuttgart 1997, the Citaro urban and rural regular-service bus has gone from strength to strength.
Unrivalled range of low-floor regular-service buses
One of the ingredients for success is the wide-ranging model line-up. The portfolio of the world’s best-selling low-floor regular-service bus comprises 28 different design variants. An ingenious modular system forms the basis for this unique variety of models. It ranges from the compact Citaro K measuring 10.5 metres in length to the CapaCity, a four-axle, 19.54 m-long, high-capacity articulated bus that was derived from the Citaro platform. This unrivalled model range enables the Citaro to cover the complete spectrum of transportation requirements of local public transport companies operating urban and rural regular-service bus routes.
Design and functionality of the Citaro perfectly matched
The hallmark features of the Citaro model family give them an unmistakable appearance. From the front end with its characteristic A-zero pillars to the three-dimensional styling of the back end with its V-shaped rear window, the Citaro has a highly distinctive design. It is also remarkable for its excellent functionality, with smooth, rounded exterior surfaces that are easy to clean and sidewalls made from lightweight aluminium, divided into segments to keep repair costs low and minimise downtimes. Apart from the front-end flap, the corner sections including the headlamp housings fold open too – making the entire front end easily accessible for maintenance work. All other maintenance points on the Citaro are easily accessible too.
The passenger compartment has revolutionised regular-service bus interiors
When passengers step aboard the low-floor bus, they are greeted by the lettering of the Mercedes-Benz brand. With its side-mounted cantilever seating and curving grab rails, the passenger compartment of the Citaro has revolutionised the interior of all urban buses, providing a role model for the entire vehicle segment. Form and function are in perfect harmony.
Comfortable independent front suspension
The Mercedes-Benz Citaro also distinguishes itself with qualities that cannot be seen, but can certainly be felt. Amongst other things, it boasts an independent front suspension, whose benefits include excellent straight-line stability, less influence on the steering from the road, a substantial saving in weight, lower unsprung masses, and improved handling and comfort characteristics in general. As a consequence, the Citaro offers a remarkably safe, composed and comfortable ride by low-floor bus standards. It also benefits from a large wheel turning angle, resulting in a small turning circle.
The unprecedented success story of the Mercedes-Benz Citaro
With over 31,000 units built, the Citaro already ranks as one of the top-selling bus models ever. No-one could have imagined such phenomenal success when Mercedes-Benz surprised the delegates at the 1997 UITP Congress in Stuttgart with the revolutionary Citaro. Even today, many in the urban bus segment still try to emulate its exemplary concept: passenger-friendly low-floor technology, a bright passenger compartment offering an excellent view through high windows, wall-mounted passenger seats in cantilever design without any floor supports to get in the way and with attractively designed, curving grab rails on the side – these were just a few of the key strengths of the new Mercedes-Benz Citaro, which it still retains today.
From the very start, fleet operators reaped the benefits of powerful, economical engines and of the Flexibly Programmed Control electronics system based on a CAN data bus architecture. This replaced miles of wiring and around 300 electronic, electrical and electromechanical components. The Electronic Braking System (EBS), disc brakes all round, ABS and side impact protection were likewise included from the outset to provide the greatest possible safety.
Continuous improvements down to the last detail
A key element in the Citaro’s recipe for success is its ongoing development. In autumn 2005, Mercedes-Benz took the model range to new heights with the second generation of the Citaro. It was kick-started with the debut of the new Citaro LE (low entry). This already included many of the modifications which were then incorporated into series production for all Citaro models in spring 2006. The front section, rear, interior and driver’s area all underwent a thorough overhaul, while the independent front suspension was also introduced for the first time.
Quick advance from Euro II to EEV
During its production, the Mercedes-Benz Citaro ran through almost the full scale of Euro emissions standards. At its premiere in 1997, the in-line six-cylinder engine with a Euro II rating represented the state of the art in emissions technology. The 2001 model version of the Citaro was powered by Euro III engines. Alternatively, the Citaro was already available with a CRT particulate filter which undercut the Euro IV particulate limits. In 2000, Mercedes-Benz presented the Citaro with natural-gas drive. This fulfilled the Euro IV emissions limits, and became available with the voluntary EEV (Enhanced Environmentally-friendly Vehicle) rating in 2002. The Citaro could also be specified with the German “Blue Angel” environmental certification in both its natural-gas and diesel variants.
Since 2006, diesel engines with the SCR emission control system have been fitted to meet the Euro IV and Euro V emissions standards. This BlueTec diesel technology produces a clear reduction in pollutant emissions, and enables fuel consumption to be lowered by a considerable margin at the same time.
Particulate emissions can be cut further by adding an optional particulate filter. This combination allowed the diesel engines to meet the voluntary EEV standard – and since spring 2010 they have been able to do so by means of internal engine measures alone, without the need for a particulate filter.
Pioneer of alternative drive systems
Apart from diesel-engined models, the range also includes the Citaro CNG with natural-gas drive. Between 2003 and 2010, 36 Citaro fuel-cell-powered buses run by twelve transport operators in countries as far apart as Iceland and Australia, covering three different continents, clocked up over two million kilometres of rigorous daily operation: it was the Citaro which first demonstrated the viability and everyday practicality of a genuine local public transport operation with zero CO2 emissions. Since 2010, the range of cutting-edge alternative drive versions has been extended by the Citaro G BlueTec Hybrid with diesel-electric hybrid drive, as well as an initial small-scale series of the rigid Citaro fuel-cell hybrid bus.
The Citaro G BlueTec Hybrid is a stepping stone en route from the diesel engine to series production of the fuel cell as a means of powering vehicles. With its serial diesel-electric hybrid drive, it enables extremely quiet, emission-free driving for several kilometres at a time.
The new Citaro FuelCELL Hybrid unveiled in early summer 2009 completes the final step to emission-free driving. Its avant-garde vehicle concept takes elements from tried-and-tested Mercedes-Benz fuel-cell buses and the diesel-electric Citaro G BlueTec Hybrid, and fuses them together with technical advances to create a new trailblazing drive system. The platform is provided by the Citaro.
The Citaro FuelCELL Hybrid emits no pollutants whatsoever and hardly makes a sound as it glides along.
Highly sophisticated production as a quality safeguard
The manufacture of the Citaro is just as pioneering. The bodyshells are assembled in the Bodyshell Centre at the Mannheim bus plant. The Citaro bodies are then primed in the Mannheim plant's cathodic dip priming facility to ensure complete corrosion protection with no gaps. The bodyshells then either move straight to final assembly in Mannheim or are transported to the assembly plants in Ligny-en-Barrois in France or Neu-Ulm to be turned into finished vehicles. Despite an urban bus's tremendous complexity, the error rate has been tending towards zero for a long time now. Nevertheless, before being delivered to the customer, every bus is put through its paces under practical conditions in real traffic on a route measuring around 100 kilometres in length.
Milestone buses supplied to Germany, Austria, Spain and Sweden
All things considered, it is little wonder that the Mercedes-Benz Citaro continues to break one record after the next. The 1000th Citaro left the factory just two years after production started, Citaro no. 10,000 rolled off the assembly line at the end of 2004. In early 2008, Mercedes-Benz delivered its 20,000th Citaro, followed by the 30,000th in summer 2010.
The Citaro can be seen operating throughout Europe’s major cities, on rural-service routes in Germany, on the tropical island of La Réunion, in Japan, China, Mexico and Australia, and even transporting pilgrims in Lourdes. In the Romanian capital of Bucharest alone, around 1000 are in service. The Citaro transports millions of passengers every day in Europe and far beyond. It forms the backbone of urban public transport, and even bridges the gap to the train in the guise of the CapaCity high-capacity bus.
Numerous special versions
The Citaro’s modular construction paves the way for numerous special versions. So, it is not unusual to see the Citaro in action as a specially converted fire-service command centre, police bus, mobile television studio or high-capacity rescue vehicle. In Poland, a Citaro is travelling around as a mobile energy advice centre. In Hanover, the 101 Citaro buses in the special livery of Üstra, the public transport operator, are as eye-catching as ever. They were put into service on the occasion of the World Exhibition in 2000 and given an unmistakable finish both inside and out.
The Citaro has even made it into the Guinness Book of Records as the world’s largest ambulance: in autumn 2009, a high-capacity rescue vehicle based on the Citaro G was deemed by adjudicators to have treatment and transport capacity for 123 people. The record-breaking articulated bus is already the third high-capacity ambulance for the sheikdom of Dubai. Apart from this trio, there are more than 300 other Citaro models also operating in Dubai. They are equipped with special insulation, special glass as well as air showers in the entrances to prepare them for the extreme heat in the Middle East sheikdom.
Platform for innovative transport systems
The Citaro is also typically used as a platform for innovative transport systems. Take, for example, the articulated Citaro GÜ buses that are operating as “road trains” in the town of Mittweida in Saxony. The buses were brought in to replace a discontinued rail link and boast a somewhat unusual specification. Passengers sit on coach-style seats which are arranged face to face, and on-board facilities include a bistro area, a toilet and space for carrying bicycles.
The 20 Bus-Way vehicles based on the Citaro G that are operating in the French city of Nantes are no less spectacular. These natural-gas-powered vehicles have their own lane. They feature an attractive, highly individual design, with side panelling that extends above the roof line, double-glazed side windows and covered wheel arches on the rear axles. Inside, LED spotlights divide the interior into two differently coloured areas. Uplighters on the window pillars, a maple wood central ceiling, grab rails made from ground stainless steel and dark blue seats give the passenger compartment its distinctive design. The driver’s cab is separated from the passenger compartment.
The “Metrobüs” BRT system in Istanbul, Turkey
The implementation of a BRT (bus rapid transit) system in Istanbul, Turkey, is no less ambitious. The “Metrobüs” travels along a 40.6‑kilometre route in dedicated lanes. At peak times, the buses run at very short intervals of less than half a minute. This results in passenger numbers of around 750,000 a day. The Mercedes-Benz CapaCity – the oversized, four-axle (19.54 m) high-capacity articulated bus derived from the Citaro – serves as the basis for this BRT system. 250 of them are already in operation there. Not only does the CapaCity offer a high transport capacity, it also achieves an exceptionally high average speed by urban bus standards of 40 km/h – all combined with extremely attractive lifecycle costs too. A trip aboard the Mercedes-Benz CapaCity in Istanbul is also highly popular due to its low-floor design and because the vehicles are air-conditioned.
Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.
OFFICIAL PRESS RELEASE
Stuttgart/Mannheim, Germany, May 20, 2011
Teams from all departments – from Development to Production to Sales & Marketing to After Sales – worked in close collaboration with one another during the development of the new Citaro. Their joint objective was to achieve supreme quality, in order to best prepare the new Citaro for the rigours of urban and rural regular-service operation
State-of-the-art design and development methods
The top quality achieved in the series production of the new Citaro is rooted in state-of-the-art development methods, such as HiL (Hardware in the Loop) and CAE (Computer-Aided Engineering). Examples for this type of quality assurance include component strength analyses, evaluation of vehicle vibrations and crash test simulations – all this and more is carried out by computer.
All safety-relevant components were analysed using the FMEA method in the early phases of development. The failure mode and effects analysis seeks to anticipate potential problems and prevent them. To put it in simple terms: the developers check everything that might go wrong in advance and undertake appropriate measures, thereby eliminating faults before they even occur. The development findings were backed up by numerous computer-aided calculations for components and assemblies as well as for the vehicle as a whole.
A laboratory bus examines production
The troubleshooting carried out during development of the new Citaro was not a purely theoretical affair, however: all the main body segments were scrutinised in rough form during the development phase when the prototype was built. It was therefore possible to examine potential cable chafing points, component accessibility or other critical issues directly on the vehicle, right from the outset.
The very first prototype of the new Citaro was already assembled on the production line so that any problems in the manufacturing process could be remedied immediately. Besides this, a special “laboratory bus” passed through each production station several times. Using this procedure, Mercedes-Benz was able to train the production workers and, at the same time, identify critical processes. Exact prototype protocols were kept to log all change requests for the bodyshop, assembly and testing, for instance. Workshops were held at regular intervals to resolve any flaws and document the progress in detail.
Testing under the toughest conditions on test rigs and the road
Individual components and assemblies, as well as complete buses were put to the test under the toughest conditions. The new doors, for example, were subject to endurance testing on test rigs, when they had to complete one million load cycles - the equivalent of a bus's entire service life – without any damage. Tests with seven carefully camouflaged prototypes were then conducted at the proving ground as well as on the road. Rigorous testing was also carried out in extreme climatic conditions, meaning that the new Citaro has already faced both the bitter cold of the Scandinavian winter and the searing summer heat in Spain and Turkey. The new urban bus furthermore had to prove its mettle in rough-road and endurance testing, which included a circuit of specially selected poor roads in remote regions of Turkey.
Successfully completed crash tests and pendulum impact tests in accordance with the ECE R29 standard for coaches, as well as rollover calculations based on the future ECE R66/01 standard, are testimony to the design’s high standard of safety.
The extensive programme of testing concludes this spring when new Mercedes-Benz Citaro buses will commence customer trials in everyday regular-service operation before series production gets underway.
The new Citaro: launching with rigid and articulated buses
Mercedes-Benz will be phasing in the high-volume model versions of the new Citaro over the course of 2011. The focus will be on urban and rural variants with a length of 12 metres and 2 or 3 doors, as well as the urban and rural versions of the articulated Citaro bus with 3 or 4 doors. The buses are driven by horizontal or vertical diesel engines from the OM 906 and OM 457 series in the familiar versions and power ratings. Further variants of the new Citaro will follow in 2012. The new Mercedes-Benz Citaro has been future-proofed, with all installation spaces already prepared for the future Euro VI emissions standard. The corresponding drive units will be launched at a later time. This progressive switch to the new model generation guarantees thorough testing of all versions, high quality, plus a continuous supply of vehicles without any disruption to customer deliveries. The complete range of new Mercedes-Benz Citaro models, including all rigid and articulated variants, the low-entry Citaro LE as well as the CapaCity, is due to become available over the course of 2012/2013.
Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.
OFFICIAL PRESS RELEASE
Stuttgart/Mannheim, Germany, May 20, 2011
A substantial reduction in running costs was one of the clear specifications for the development of the new Citaro. An ambitious objective, as the Citaro was already an exceptionally economical urban bus as it was. Development work focused on the maintenance costs. With the launch of the new model, the maintenance intervals for the automatic transmission and rear axle have now been extended from 120,000 km to 180,000 km. The smaller details help to cut costs too: the air intake for ventilating the driver’s cab is now fitted with larger filters, which have longer replacement intervals.
Risk of damage from minor knocks greatly reduced
The repair of the typical minor damage sustained by urban buses in hectic traffic also generates costs, however. This was another point the developers turned their attention to. The front overhang features shoe-shaped scuffing protectors made from glass-fibre-reinforced plastic with a bolt-on, replaceable design. These protect the hem profiles of the bus when drawing into bus stops or swinging out over embankments, as can occur on rural-service routes, for example. The flexible bumper corners made from elastic glass-fibre-reinforced plastic on the rear bumper and wheel arches also help to lower repair costs.
LED lighting reduces power consumption and lasts longer
The numerous LED lights on both the inside and the outside of the new Citaro bring about a noticeable reduction in power consumption. They furthermore generally last for as long as a bus’s service life, largely doing away with the need to carry out tedious, time-consuming minor jobs like replacing faulty bulbs for the whole of the Citaro’s lifecycle.
Numerous other details likewise help to further reduce the amount of maintenance work required. There is now a sensor to measure the battery’s voltage, for instance, which works together with a controller to keep the voltage at a consistently high level, increasing battery life significantly. The capacity of the windscreen washer reservoir behind the front fascia has been increased from 8 to 20 litres as part of the model change, reducing to a minimum the frequency with which the washer fluid has to be topped up.
Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.
OFFICIAL PRESS RELEASE
Stuttgart/Mannheim, Germany, May 20, 2011
The engines for the new Mercedes-Benz Citaro are based on BlueTec diesel technology. The wide-ranging choice of engines for the Citaro covers the full spectrum of power requirements. The OM 906 hLA turbocharged diesel engine is a particularly compact and lightweight six-cylinder unit with a displacement of 6.37 litres, an output of 210 kW (286 hp) and a maximum torque of 1120 Nm. Alternatively, there is the OM 457 hLA six-cylinder engine with a 12 l displacement in a choice of two power ratings: 220 kW (299 hp) and 260 kW (354 hp) with maximum torques of 1250 Nm and 1600 Nm respectively. All of the engine variants stand out for their high pulling power from low rev speeds. This is of particular importance for enabling the bus to pull away dynamically in city traffic, even when full to capacity.
EEV emissions rating even without particulate filter
All engines are Euro V compliant as standard. The engines can furthermore be specified in a version that meets the most stringent voluntary emissions standard that currently exists – the EEV (Enhanced Environmentally-friendly Vehicle) standard. The new Citaro achieves EEV compliance by means of internal engine measures alone without the need for a particulate filter – further evidence of the enormous potential of the efficient, eco-friendly BlueTec diesel technology and its viability for the future. EEV with no filter means reduced costs for procurement as well as maintenance. Further benefits include the lower kerb weight and reduced space requirements, which in turn increases the number of seats. A particulate filter can, of course, be installed as an option. Power transmission is handled by fully automatic torque-converter transmissions made by Voith and ZF. The most up-to-date versions of both are fitted in the Citaro to maximise efficiency. With a choice of engine, transmission and matching final drive ratio, the new Citaro takes to the road with a customised drivetrain, just as its predecessor did.
Further reduction in fuel consumption
A new, electronically controlled air compressor is employed on the articulated Citaro bus with the vertically mounted OM 457 LA engine. This is an EAPU (Electronic Air Processing Unit) that combines the compressed-air drier, pressure governor, four-circuit safety valve and pressure sensors into a single component. The compact construction simplifies assembly and reduces the number of lines required. Where possible, the electronically controlled air compressor operates when the Citaro G is in overrun mode to save fuel. To ensure this is the case as often as possible, the system pressure for the suspension and door operation has been increased from 10 to 13 bar with the introduction of the new air compressor. This produces greater air reserves in day-to-day operation and saves fuel.
Detailed improvements to comfort suspension
The chassis on the new Mercedes-Benz Citaro again excels with exceptional comfort and handling safety thanks to its independent front suspension. In this respect too though, the new Citaro has now gone one better, especially from the driver’s point of view. The reworked steering has improved steering-wheel return, for instance – a key consideration for urban regular-service buses which have to turn so frequently.
Supreme safety levels thanks to innovative assistance system
A new assistance system is making its debut in the low-floor bus and in the Citaro simultaneously: for the first time, the Electronic Stability Program (ESP) is available for an urban regular-service bus. The Mercedes‑Benz Citaro is taking safety technology for urban regular-service buses into a new era with this innovative feature – thereby emulating its predecessor, which also set new benchmarks on its launch.
Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.
OFFICIAL PRESS RELEASE
Stuttgart/Mannheim, Germany, May 20, 2011
The developers have completely remodelled the driver’s workstation, and the cockpit now takes ease of operation, ergonomics, instrumentation and comfort to new heights for regular-service buses.
A new driver’s door leads into the cockpit area
Even the door to the driver's cab has been redesigned. The door is now hinged at the rear and opens from the front, allowing drivers to move in a straight line between the front door and their workstation for particularly fast entry and exit. The developers also took the opportunity to improve the stowage facilities in the door. Drivers will now find a larger compartment for their bag, for example, as well as an extra compartment for a drinks bottle. The partition screen for the driver’s cab has been given a new look too, and is now larger and curves further forward. Instead of the grab rail previously fitted at the front of the partition screen, there is now a grab handle on the side.
For the first time, the new Citaro can be factory-fitted with another new development – an optional driver protection door. This door has a modular design based on the standard door. Depending on requirements, a number of variants are available, which offer graduated levels of protection by forming a screen between driver and passengers.
At eye level with passengers
The driver’s seating position has been altered too. The height of the driver’s pedestal and seat has been increased by 60 mm altogether. This gives the driver the psychological advantage of being at eye level with the passengers boarding. At the same time, the raised seating position affords a better all-round view, for example of the traffic in front. To maintain the exemplary view outwards and upwards, the windscreen has likewise been raised by 60 mm. The destination display, meanwhile, has been moved up by a whole 72 mm, for even better visibility when looking up and to the side, for example at traffic lights. The lowering of the window sill at the side is also beneficial to the driver. The development team has made the pedals more ergonomic to operate too.
Attractive instrument panel, handy steering-wheel control pad
The completely newly developed instrument panel in the new Citaro meets the specifications of the Association of German Transport Operators in terms of both its construction and adjustability, as does the steering wheel. However, the developers have succeeded in creating considerably more knee room and foot room for the driver with the new, elegant design. The upper section’s light-grey colour adds to the cheerful, welcoming impression.
The cockpit comprises large, clearly arranged dials for road speed and engine speed, with a grey background. The strip of indicator and warning lamps between the two dials has now been replaced by a colour display showing a multitude of supplementary information.
The display is operated using the standard control pad on the new steering wheel. The two-dimensional menu navigation is very clearly structured, and also allows basic operation of the radio or two-way radio, for example. The steering wheel, its control pad, as well as the colour display, are the same as those fitted in the current range of Mercedes-Benz touring coaches.
Logically arranged switches and buttons
The buttons and switches in the Citaro’s cockpit have been repositioned based on the latest ergonomic findings. As a result, the lower array of switches on the driver’s right-hand side (on left-hand-drive vehicles) consists solely of the door-control buttons that are in constant use in daily operation. The control buttons for the automatic transmission, which are generally used less frequently, are now positioned further forward in a separate horizontal strip. The location of the light switch is also worth noting – it continues to be placed on the left of the cockpit, but no longer on the front face of the instrument panel. Not only does the new prominent position much further forward make the switch easily accessible, but the driver also has the switch setting in their field of vision at all times. The repositioning also frees up extra legroom.The new Citaro is prepared for all eventualities. The regular-service bus’s instrument panel has been constructed so sturdily that it can support additional items of apparatus on both left and right, each weighing up to 2.5 kg. Mounting adapters as well as cable bushings can be factory-fitted as special equipment for this purpose, allowing customer-specific equipment to be integrated far more neatly than before.
Further improvements to driver's workstation
Depending on which door variant the transport operator chooses for the driver’s cab, either two or four additional DIN slots are provided on the right-hand side (on LHD vehicles) within the driver’s reach and vision, offering even greater versatility and flexibility for fitting additional equipment. Accessibility to the existing slots in the overhead equipment cabinet has now been improved by a new flap on the side. Up to four devices can also be fitted in the slots in the frame, where they are also easily accessible and legible. The loudspeaker for the driver’s area is also housed here, while the monitor for the optional interior or exterior cameras is mounted so that it interlocks with the base of the overhead cabinet.
The window sill next to the driver was also restyled as part of the Citaro’s redesign. The controls there are now placed directly within the driver’s reach and vision, while the stowage facilities here have also been remodelled. LED bulbs are now used to illuminate the driver’s area.
Ventilation system completely redesigned
The ventilation system for the driver’s area is also new. The electrically opening window section is now positioned at the front, so that drivers can now enjoy a direct flow of fresh air. This also makes it easier to reach the offside exterior mirror from the driver's seat. Air can also enter through two large circular air vents in the instrument panel.
There is now room for a larger pollen filter behind the enlarged air intake grille positioned at the side immediately behind the driver’s seat. The new ventilation unit behind the driver’s seat ensures a high airflow rate into the driver’s cab. The front box for ventilating and heating the driver’s area has been furthermore repositioned in the centre to ensure that the entire windscreen can be demisted even more evenly. As on the outgoing model, it is also electrically heated.
New options to aid the driver
The new large and extra-powerful halogen headlamps help the driver to see in poor visibility, thereby increasing driving safety. The list of options includes LED daytime running lamps, front fog lamps with a cornering light function and even bi-xenon headlamps.
The compartments surrounding the cockpit have been rearranged too. Any objects that are found on the bus can now be stored in an enclosed compartment at the front right of the instrument panel (on LHD vehicles). Not far away is the fire extinguisher, positioned where it is close to hand. Items of emergency equipment such as the first-aid kits are now housed where they are easily visible and accessible in a compartment inside the driver's cab. Like all the other compartments, this can be quickly and easily reached by the driver, but is protected from unauthorised access by passengers alighting from the bus.
Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.
OFFICIAL PRESS RELEASE
Stuttgart/Mannheim, Germany, May 20, 2011
The Citaro already set new standards when it was first launched in 1997, with a passenger compartment that was as cheerful as it was practical. The new Citaro follows in this tradition by setting another milestone in the development of regular-service buses with a multitude of innovations.
New doors save weight and increase strength
The new inward-swinging doors, manufactured in-house, have a lightweight, low-maintenance design, and feature an optimised rubber seal at the bottom for a snug fit when closed. The new sealing concept produces a virtually air-tight seal around the doors, largely eliminating wind noise in the vehicle interior in the process. The new doors stand out for their low weight, sturdy frames and highly accurate fit. The door leaves are individually controllable and are operated separately. Alternatively, the Citaro can be equipped with a new pivot-and-slide door at the front entrance too, which is available exclusively for the Citaro. This door is inclined slightly outwards as it slides forwards, allowing it to pass the nearside exterior mirror without touching it. The characteristics of the new pivot-and-slide door likewise include low weight and high stability.
Lower, well-illuminated entrances
The passenger compartment of the new Citaro has a particularly inviting feel to it. The pleasant experience for passengers begins at the bus stop thanks to the use of broad LED light strips to light up the entrance and exit areas brightly at all doors, both inside and outside the bus. A large plaque bearing the brand logo and lettering, which is integrated into the new door leading to the driver's cab, lets all passengers know as soon as they step on board the new Citaro that they are taking a seat in a Mercedes-Benz.
Sophisticated lighting technology for increased comfort and safety
The new Citaro’s passenger compartment stands out for its bright and cheerful design. This applies to both the colour scheme and the interior lighting concept. The ceiling lamps have multidimensional lenses, meaning their light doesn't just shine down directly, but also reflects off the roof hatches to produce an indirect lighting effect. LED bulbs can be fitted in place of the standard fluorescent tubes as an option. In future, it will be possible to have extra light fittings installed around the edge of the ceiling. This lighting technology can be used to create quiet zones and reading corners within the seating area. The good lighting levels will have the additional effect of reducing the risk of vandalism at the rear of the bus.
Lighting units that can be integrated into the new grab rails on the Citaro are likewise available. The upright grab rails basically feature the same outward-curving shape taken from the predecessor, which served as a model solution for the entire industry. The new uniform distribution achieved by attaching the grab rails to a continuous overhead section to form just two lines gives the interior a more orderly appearance. Straight grab rails are fitted at the front. They are positioned further apart here, giving passengers boarding the bus the impression of more space. The horizontal grab rails are now mounted in front of the vertical rails, which also has the effect of giving the passenger compartment a more tranquil appearance and creates a line for the eye to follow when looking around the interior.
Innovative grab rails with advertising and lighting
The horizontal grab rails are made from extruded aluminium sections and are oval in section. This, together with their larger diameter, makes them particularly easy to grip. The new shape furthermore allows lighting elements as well as exchangeable advertising inserts with clip fasteners to be integrated into the grab rails, paving the way for a brand new form of advertising. The new, wraparound stop-request buttons are easier to find, especially for passengers with impaired vision.
The partition behind the driver’s cab as well as the outer ceiling flaps can now be used as advertising space too. There is also the option of route displays which can be integrated into the outer ceiling sections. Pre-fittings for monitors with a 48.26 cm or 55.88 cm screen diagonal are furthermore provided behind the cross-duct and in the rear section of the bus for information and advertising purposes.
Smaller cross duct, new stowage facilities
The cross duct between the front entrance and the main passenger compartment is much flatter on the new Citaro. This has the advantage of increasing headroom, enhancing the sense of spaciousness and optimising the driver's view of the passenger compartment through the interior mirror. Also new to the passenger compartment are the stowage shelves with closed bases instead of the grilles that were previously used around the grab rails. The stowage shelves and frame can now be painted in different colours.
The modified wheelchair bay that is optionally available offers added protection for passengers with reduced mobility thanks to a raised bulge on the grab rail and a glass retaining wall. Its design blends in harmoniously with the rest of the new Citaro interior. The new and distinctively styled glass partitions are screen-printed to make them easier to see. The shape of the glass panels increases the distance between them and the grab rail, making it easier for passengers to hold on.
A new inner ceiling facilitates ventilation
The new centre section of the ceiling running the length of the passenger compartment has a composed, uniform design with an even perforation pattern that extends into the ceiling segments underneath the roof hatches too. This perforated ceiling allows the passenger compartment to be ventilated evenly over a large area. Fresh air enters through the ceiling segments underneath the open roof hatches. These can be raised open electrically and close automatically whenever the windscreen wipers are operated or the engine is switched off. Like the outgoing model, the new Citaro also offers the option of a highly effective ventilation system with overhead ducting and built-in heater – an unusually elaborate concept in the urban regular-service bus segment. The interior is heated as standard by new sidewall heaters, with the option of convector heating.
Compact air-conditioning system lowers procurement and running costs
Mercedes-Benz now offers the Citaro rigid bus with a new compact air-conditioning system as an additional option to bridge the gap between the familiar ventilation and air-conditioning systems. It takes the form of individual independent units, which are positioned over the roof hatches and do not require any additional cabling other than for supplying power. Thanks to its slight cooling effect combined with uniform movement of the air, the system can maintain a comfortable interior climate at average summer temperatures for Central Europe. The system is regulated according to the outside temperature. Both procurement and running costs are lower than with a conventional air-conditioning system, where the high cooling capacity is attained regardless of the exterior temperature. The refrigeration capacity is 3.8 kW per unit.
The proven seating concept has been retained
The new Citaro has adopted the previous model’s proven seating concept with cantilever mounting. The seats are manufactured in-house. The City Star Eco version is fitted as standard in urban buses, while the Citaro Ü comes equipped with the Inter Star Eco rural-service seat, in view of the longer time that tends to be spent in the vehicle. There are many different variants to choose from for both the seating design and the arrangement of the seats in the passenger compartment.
Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.
