There's good news for those getting bored of strolling around town in the Bluetec E-Class because Mercedes-Benz is announcing the U.S. availability of the 2009 GL320 BlueTEC, ML320 BlueTEC and R320 BlueTEC. In an effort to be hip and trendy with the U.S. market, Mercedes-Benz faked a campaign speech, but in all reality it looked more like a riot. As the two BlueTEC ML320s rolled onto the stage along came with it a nice sample pool of a typical campaign supporters who really, really care about BlueTEC diesel technology including one special older lady (pictured)—see: cougar—who acted out her dreams of becoming an auto show booth babe by waving her hand up and down the vehicle as people took pictures.
The BlueTEC diesel engines in the three respected SUVs is a 211 HP 3.0-liter V6 turbodiesel. The BlueTEC gives 17 mpg in the city and 23 on the highway and the three will be available later this Fall.
The cleanest solution - Mercedes-Benz brings the world's first diesel SUVs with AdBlue injection to the U.S.
• Liquid urea injection ensures the cleanest exhaust emissions ever
• Fulfills stringent U.S. BIN5 standard
• High performance, fuel economy and comfort for a great driving experience
In October 2006, Mercedes-Benz was the first manufacturer to begin a BlueTEC offensive within the U.S. passenger vehicle segment to coincide with the introduction of ultra low-sulfur diesel fuel. The E320 BlueTEC was a huge success right from the beginning and was voted "2007 World Green Car of the Year". Mercedes-Benz is now pushing forward with this initiative with the R, ML and GL320 BlueTEC - the world's first three diesel SUVs which not only meet the particularly demanding targets specified in the U.S. BIN5 standard, but are also positioned to fulfill forthcoming stringent EU6 emissions legislation. This puts them well within all current emissions standards for diesel passenger vehicles worldwide.
With characteristics such as enormous pulling power, fuel economy and high performance, the diesel engine has proven itself as an attractive alternative to gasoline engines even in the U.S., during times of increasing fuel prices and growing sensitivity towards CO2 emissions. In the land of large minivans, pickups and SUV's, where driving habits generally feature consistent highway speeds and long distances cross-country, the benefits of diesel present an attractive solution. At the same time, U.S. lawmakers have set extremely stringent emissions legislation for diesel drivetrains. This is why Mercedes-Benz chose the U.S. for the worldwide debut of its in-house developed BlueTEC technology in the E320 BlueTEC, as well as for the launch of its latest BlueTEC system with AdBlue injection (technical name - Urea SCR System). This innovative driveline technology enables large, high-performance SUVs to meet the limits set by the U.S. BIN5 standard.
Impressive performance, excellent fuel economy and the lowest emissions
The powerful V6 turbodiesel engine under the hood of the new GL, M and R-Class BlueTEC models demonstrates that excellent fuel economy and the lowest emissions are within the grasp of large SUVs. It has an output of 210 bhp and 398 lb.ft. of torque, while boasting outstanding fuel economy. The GL320 BlueTEC achieves an estimated 24 mpg, which represents a fuel consumption benefit of approximately 20 to 40 percent over a comparable gasoline engine, and makes the Mercedes-Benz GL320 BlueTEC by far the most fuel efficient full size SUV in the U.S.
The six-cylinder diesel required a few modifications for its application in the new ML320 BlueTEC, GL320 BlueTEC and R320 BlueTEC with AdBlue injection. The piston cavity profile was reworked for an improved fuel/air mix, while its compression ratio was reduced from 17.7 to 16.5. The VNT turbocharger was also optimized and reconfigured, as was the ECU. All three new SUVs are equipped exclusively with the seven speed 7G-TRONIC automatic transmission.
BlueTEC leads to drastic reductions in NOx emissions
As a modular concept for the effective reduction of fuel consumption and emissions in diesel vehicles, BlueTEC technology developed by Mercedes-Benz encompasses a range of complementary technical initiatives designed to minimize engine emissions, as well as to provide effective exhaust gas after-treatment. A systematic, step-by-step approach reduced all relevant emission factors to an absolute minimum, with the application of technologies such as oxidization catalysts and particulate filters. An important goal, however, is the drastic reduction of NOx emissions - the single exhaust component of a diesel engine that remains, by its very nature, higher than that of a gasoline engine.
In order to address this issue, Mercedes-Benz has developed two versions. In the E320 BlueTEC sold in the U.S. and its European variant, the E300 BlueTEC, oxidization catalysts and particulate filters are combined with a long-life NOx storage catalyst and an additional SCR catalyst (Selective Catalytic Reduction). The second BlueTEC version is used in the new GL320 BlueTEC, ML320 BlueTEC and R320 BlueTEC. In these new models, AdBlue - a harmless, liquid urea solution - is injected into the exhaust. This releases ammonia, which, in the SCR catalyst downstream, converts up to 80 percent of NOx emissions into harmless nitrogen gas and water.
The individual components of this innovative exhaust technology include:
• Optimization of engine combustion processes in order to reduce internal emissions as much as possible. This includes electronic engine management, four-valve technology, third generation common-rail direct injection with piezo injectors, variable geometry turbocharger with exhaust gas recirculation.
• Oxidization catalysts minimize emissions of carbon monoxide (CO) and unburnt hydrocarbons (HC).
• The particulate filter, which has been standard in all diesel-powered Mercedes-Benz passenger vehicles in many countries since summer 2005, reduces particulate emissions to a virtually undetectable level that is significantly below current EU4 particulate limits (0.025 gram/kilometer). This also fulfills applicable U.S. requirements.
• Nitrogen Oxides are reduced via a NOx storage catalyst in combination with an SCR catalyst, or via AdBlue injection in combination with an SCR catalyst. These highly effective methods of exhaust gas after-treatment enable a reduction in NOx emissions in BlueTEC vehicles of up to 80 percent.
AdBlue injection is particularly beneficial for large vehicles
The choice between a NOx storage catalyst or AdBlue injection for effective reduction of NOx emissions is dependent upon the individual vehicle design, as well as the respective market conditions. AdBlue technology is beneficial for large sedans, pickups and SUVs because it means that the engine no longer needs to run periodically on a rich combustion cycle in order to purge the NOx storage catalyst, which removes harmful nitrogen oxides from the exhaust gas. Large vehicles with higher fuel consumption would require frequent purging, which would ultimately lead to more fuel consumption.
The urea SCR process requires the injection of AdBlue reducing agent into the exhaust line. AdBlue is an aqueous urea solution, which is stored in a small, separate tank. Upon injection into the hot, pre-treated exhaust gas, the AdBlue solution breaks down into its component parts, water and urea. Above temperatures of around 338 degrees Fahrenheit, the urea is converted into Ammonia (NH3) - the active agent in this process. The ammonia is stored within the catalyst and reduces the nitrogen oxides into harmless nitrogen gas as soon as NOx-bearing exhaust gases pass through the catalyst.
The ECU manages the AdBlue injection to ensure that there is always sufficient ammonia stored in the SCR catalyst without flooding it. This is monitored by a NOx sensor.
One small AdBlue tank is all it takes
The urea solution is stored in a dedicated tank on-board the vehicle, and is carried to the charge module via a feed pump. The tank was designed such that a refill of AdBlue is necessary only at regular maintenance intervals. In the R320 BlueTEC and the ML320 BlueTEC the tank holds approximately 7 gallons, while in the GL320 BlueTEC it has a capacity of 8.5 gallons. This is sufficient to ensure that no extra trips to the dealership are required, even under more extreme operating conditions with higher AdBlue consumption, such as towing. The customer plays no direct role in refilling the AdBlue. Service intervals are 10,000 miles.
New styling and increased equipment levels
With its innovative R, M and GL-Class BlueTEC models, Mercedes-Benz is not only demonstrating the potential of diesel drivetrains, but is also offering tailor-made solutions for upscale demands with the most extensive SUV range in the premium segment. The R-Class offers exceptional comfort on long-distance journeys, and the segment's most generously proportioned and flexible interior, with seating for up to seven. The M-Class is the most successful Mercedes-Benz sports utility vehicle and started the trend towards modern premium SUVs. And, with the GL-Class, Mercedes-Benz leads the entire SUV sector in terms of first class occupant comfort under all conditions - both on and off road.
Standard equipment has been expanded substantially across the M, R and G-Class ranges. They all now come with the unique PRE-SAFE® predictive occupant protection system and Active Front Head Restraints, as well as a new telematic system developed by Mercedes-Benz, with improved user interface, higher performance and a host of new functions.
More performance, more comfort - new generation telematics
The SUVs now come equipped with a new generation telematics system developed by Mercedes-Benz. It boasts a substantially improved user interface, high performance and a host of new functions. A hands-free system with Bluetooth technology is integrated as standard, as is an aux-in port for connecting mobile audio devices such as an iPod. A new Universal Consumer Interface is available as an option, for connecting an external music storage device with the SUV's on-board electronics and operating system. This feature allows track titles to be displayed on both the instrument cluster and on the color screen in the center console, and enables them to be selected via the keys on the multi-function steering wheel. The battery of the audio device is simultaneously charged.
Customers may choose from a range of three head units. All of them include features such as a color display, a double tuner for improved radio reception, speed-regulated volume control, a keypad for inputting phone numbers and radio frequencies, as well as a Bluetooth interface that enables wireless connection to the hands-free system. Customers in the U.S. can also order an HD radio or SIRIUS satellite radio as an option. With its new generation telematics, Mercedes-Benz is also offering the optimized Voice Recognition system as an upgrade.
Passengers can also enjoy rich, spatial surround sound courtesy of the optional newest generation harman kardon® Logic7® sound system. With increased performance and a digital signal processor (DSP), it guarantees outstanding clarity and listening pleasure.
For those in the rear, a new entertainment system is available, complete with two large 8- inch screens and a DVD player, as well as two wireless headsets for greater freedom of movement and a remote control.
Unique safety equipment as standard
When it comes to safety, Mercedes-Benz vehicles have always led the field in the SUV segment. The R, M and GL-Class now come with the PRE-SAFE® predictive occupant protection system and Active Front Head Restraints as standard.
Mercedes-Benz is the benchmark in diesel cars and trucks
70 years ago, Mercedes-Benz was the first manufacturer to implement Rudolf Diesel's combustion principle in a passenger vehicle. This technology is significantly more efficient than the gasoline engine and has been optimized over many years. A decisive technological leap in 1997 played a significant role in the development of the modern diesel engine - the introduction of common-rail direct injection in combination with four-valve technology. Since then, the abbreviation CDI stands not only for unparalleled fuel economy, but also for a huge increase in torque.
If there were any disadvantages of a diesel versus a gasoline engine it was in certain emissions - primarily soot particulates and nitrogen oxides. However, as of fall 2003, Mercedes-Benz had also tackled the particulate issue, with the introduction of the maintenance-free particulate filter. And even though nitrogen oxide emissions have been reduced by approximately 75 percent over the past 15 years through engine-based initiatives, Mercedes-Benz was still not satisfied. With its innovative BlueTEC technology, which was launched in a passenger vehicle for the first time in 2006 in the U.S., Mercedes-Benz hi-tech diesel powertrains fulfill the world's most stringent exhaust standards. AdBlue injection now makes the new ML320 BlueTEC, R320 BlueTEC and GL320 BlueTEC the world's cleanest diesel SUVs.
Photos by Elizabeth Bordo