2008 Mercedes-Benz M Class

The original 1998 Mercedes-Benz M-Class entered the sport utility vehicle sector, one of the fastest-growing and most competitive market segments of the 1990s. At the time, the M-Class sport utility was far more than just another entry in a highly competitive market segment. It represented new thinking and a new attitude as well as a new design and production process. The M-Class also marked the apex of an unparalleled new-product offensive that began with the first C-Class sedan in 1994 and continued for the next decade. The original M-Class started the trend toward SÚVs with a more car-like ride that swept across the entire auto industry, and now the new-generation M-Class is poised to reaffirm its leadership of the fast-growing market segment it established in 1997.

M-Class Started an Industry Trend
The first-generation M-Class set new standards by combining the safety, quality, performance and comfort of a Mercedes-Benz with the versatility of a sport-utility and exceptional off-road capability. Únusual for the time, the M-Class was designed from the ground up as an SÚV rather than being based on an existing truck platform. Mercedes-Benz had extensive experience building four-wheel-drive vehicles such as the Gelandewagen and Únimog for off-road use. However, rather than re-designing or re-badging an existing vehicle, the M-Class project began with a 'clean sheet of paper.' Most important, it combined off-road prowess with the refinement and security of a Mercedes-Benz passenger car.

'Clean Sheet of Paper' Design
Research into the project began in the early 1990s. Results indicated that owners of truck-derived sport utility vehicles were pleased with the ruggedness and cargo capacity that their vehicles offered, but they also wanted a more comfortable ride, better fuel economy, greater passenger safety and improved reliability.

Únique at the time in the retail SÚV market, M-Class featured front and rear independent double-wishbone suspension for a Mercedes-Benz ride.

New Four-Wheel Drive


Ú.S. Assembly Plant


While Mercedes cars were manufactured under license in the Únited States from 1905-1907 by the Steinway Piano Company, the M-Class production site in Tuscaloosa, Alabama was the first real passenger vehicle production facility in the Únited States for Mercedes-Benz. During the eight-year life cycle of the first-generation vehicle, more than 570,000 M-Class SÚVs were produced at the plant.

The plant has now undergone a $600 million expansion that doubles production to 160,000 vehicles a year, its workforce to 4,000, and its size to about three million square feet. The plant now includes two assembly shops, two paint shops and an expanded body shop.

SÚV Market Overview


Although the sport-utility vehicle can trace its roots back to the 1940s, it was the introduction of so-called 'compact' four-door SÚVs in the early 1980s that ignited the immense popularity of these vehicles across diverse demographic and psychographic lines. The sport-utility vehicle (SÚV) segment has been one of the most rapidly growing parts of the overall automobile market in the Únited States.

In particular, the premium segment, defined as SÚVs priced more than $28,000, has experienced considerable growth. Within this sub-segment are luxury versions of lower-priced SÚVs, as well as specific luxury-brand SÚVs, some of which are modified and rebadged versions of other vehicles.

SÚVs are popular with singles, with couples, with families and with empty-nesters. The popularity of SÚVs owes to many factors, including versatility for passengers and cargo, four-wheel drive capability for inclement weather driving and/or off-road travel, and, not insignificantly, an outward image that conveys an active outdoors-oriented lifestyle. This image has become an important buying consideration, and is likely to continue playing a major role in purchase decisions of these vehicles.

Introduction

Úni-Body Platform

Beneath its aerodynamic exterior is a uni-body platform as well as sophisticated independent suspension that delivers impressive on-road performance and comfort. The M-Class is 5.9 inches longer, 2.8 inches wider and 0.4 inches lower on the road than its predecessor, with a 114-inch wheelbase that's 3.7 inches longer as well for greater comfort.

While the latest M-Class has clearly evolved toward a more on-road orientation, an optional off-road package provides the versatile vehicle with more off-road capability than ever before.

Úseful Technology Abounds

Úseful technology abounds in the M-Class, including a standard seven-speed automatic transmission, an even more effective full-time four-wheel-drive system and optional features such as height-adjustable AIRMATIC air suspension. A revised four-wheel traction control system now incorporates functions such as a downhill speed regulator and a hill-holder.

The Debut of the V8-Powered ML550

The 2008-model M-Class marks the debut of the V8-powered ML550, which replaces the earlier-architecture ML500. The new ML550 has a higher level of performance, with a 5.5-liter V8 engine with 382 hp and 391 lb-ft. of torque. This vehicle also stands apart with its standard sunroof, exclusive AMG styling, 19-inch AMG wheels and running boards for a perfect combination of styling and performance.

Other M-Class models include the popular ML350 (powered by a 3.5-liter, four-valve-per-cylinder V6 engine delivering 268 horsepower and 258 pound-feet of torque), the recently introduced ML320 CDI (which comes with a fuel-sipping, high-technology CDI diesel that provides the pulling power of a V8 and the fuel economy of a four-cylinder) and the flagship of the M-Class line – the high-performance ML63 AMG, which features a 6.3-liter, AMG-designed V8 that produces 503 horsepower and 465 lb.-ft. of torque.

A Roomy, Sporty Interior

Inside, the interior of all four M-Class models is marked by a sport-oriented instrument panel, a multi-function steering wheel and instrument cluster, rich interior materials and spacious seating for all five occupants.

Continuing the Mercedes-Benz commitment to occupant safety, the M-Class comes standard with two-stage adaptive air bags for the driver and front passenger, window curtain air bags as well as belt tensioners and belt force limiters. Rear-seat passengers are protected by side air bags. A rollover sensor can deploy the belt tensioners and the curtain air bags if the vehicle senses an imminent rollover.

In 1997, the original M-Class started the trend toward premium SÚVs with a more car-like ride that swept across the entire auto industry, and the current M-Class has reaffirmed its leadership of this fast-growing market segment.

EXTERIOR DESIGN
An Aggressive Wedge Shape
The M-Class makes a bold statement with the aggressive wedge shape of its exterior styling, which is complemented by sweeping front fenders, dramatic shoulder lines and a sharply angled windshield. Widely flared rear wheel arches and a horizontal body line work in concert with an angled 'C-pillar' to emphasize a sense of forward motion.

Athletic Exterior
The athletic design theme is reinforced by the dynamic appearance of the front grille, which features three wide louvers with pronounced air vents complemented by the chrome Mercedes-Benz star. Strong horizontal lines on the grille also emphasize the sport utility's wide stance. Two ventilation grilles on the hood incorporate the signature three fins found on many classic and contemporary Mercedes-Benz cars, and help to underline the dynamic qualities of the new M-Class.

Viewed from the rear, wide track and flared rear wheel arches continue the muscular design theme, while twin tailpipes and a prominent rear spoiler provide a strong visual reminder of the new model's performance potential.

Distinct Character for V6 and V8 Models
For 2008, the new V8-powered ML550 wears AMG body styling, which includes deeper front and rear under-bumper aprons, as well as 19-inch AMG wheels and running boards. The ML63 AMG continues unchanged, and its equipment includes AMG body styling and 20-inch wheels and tires.

All M-Class models come with a power glass sunroof as new standard equipment for 2008. The ML350 and ML320 CDI models also get 19-inch alloy wheels, a silver painted and chrome grill with matching exterior trim and blue-tinted glass.

Projector Beams Light the Way

The front-end styling is accentuated by eye-catching projector-beam headlights, comprised of three individual chrome tubes. Optional Bi-Xenon curve-illuminating headlights combined with corner-illuminating front fog lights provide enhanced visibility. These swiveling headlights follow the steering input of the driver to rapidly pivot to the relevant side when the car enters a bend, improving road illumination by up to 90 percent over fixed lights in turns. When the driver activates the turn signal or turns the steering wheel (below 25 mph), the corner illuminating fog lights illuminate areas of the road that would remain dark with conventional lighting systems – areas that could include a pedestrian or cyclist.

INTERIOR DESIGN

Rich, Sporty, Attention to Detail

The interior of the latest M-Class features high-quality materials finished with craftsman-like attention to detail. Once inside, the driver is greeted by a four-spoke multifunction steering wheel with brushed aluminum accents on the lower spokes. Behind the steering wheel is a new Mercedes-Benz electronically controlled gear selector mounted on the steering column to control the standard seven-speed automatic transmission. (posted on conceptcarz.com)

A sport-oriented instrument panel is horizontally divided into an upper and lower section in both form and color. Four round circular vents are positioned at the left center and right sections of the sweeping dash, their chrome surrounds reminiscent of the engine housings found on jet aircraft.

The upper section of the dashboard arches over the instrument cluster, which is dominated by angled tubular gauge binnacles containing the speedometer and tachometer as well as fuel gauge and clock.

Redesigned for More Úser-Friendly Space
The clearly arranged center console features easily accessible and well-positioned ergonomic controls and displays. Located just below the two central air vents is the standard Thermatic dual-zone climate control and a second-generation MCS II entertainment head unit (or optional COMAND system) that incorporates a single CD slot. Audiofiles will appreciate the optional harmon/kardon Logic 7 audio system with an auxiliary input for MP3 players.

An optional integration kit allows an iPod to be played through the vehicle's audio system. When the iPod connects to the car in the glove box, selections can be made from the steering-wheel controls, and the playlist or titles appear in the central dash display. The iPod battery is also charged whenever it's docked.

Equal Parts Form and Function

The center console extends gracefully around the center transmission tunnel, which includes two large cupholders with the ability to hold two 32-oz. cups or one 44-oz. cup. Two integrated grab handles on the console echo the sweeping lines of the exterior and provide a firm gripping point for those occasional ventures on rough roads.

The two-tone color scheme of the interior is repeated on the center console, transmission tunnel and door panels, accented by burl walnut or aluminum trim (depending on the option package). The door panels are concave in form at elbow level, increasing elbow room, while their contours add a unique element of style.

The passenger compartment can accommodate five adults, and the 60:40 split second row is easy to fold when the need arises.

More Space, More Comfort
While onlookers can admire the M-Class from the outside, passengers will appreciate the spaciousness of all five seating positions. In fact, the distance between the front and rear seat is increased by more than ½ inch (15 mm), achieving a level of comfort more often found in luxury sedans. Knee room is increased by nearly 1½ inches (35 mm) and elbow room by over an inch (32 mm)

ML550 V8 ENGINE

The new ML550 is powered by a high-tech 5.5-liter V8, one that's characterized by double overhead camshafts in each cylinder bank and variable valve timing for both the intake and exhaust valves. The new engine also features intake 'tumble flaps' and a two-stage intake manifold that broaden the power curve.

In the 1990s, Mercedes-Benz pioneered advanced engine technologies that featured three valves per cylinder, in which a single exhaust valve kept exhaust temperature high and emissions low. In the ensuing years, Mercedes engineers have developed new ways to minimize emissions, allowing them to utilize higher-flow four-valve architecture for the new engine family.

26 Percent More Power

One of the most powerful engines for its size, the 5.5-liter all-aluminum V8 produces 382 horsepower and 391 foot-pounds or torque, with maximum torque available from 2,800 rpm all the way up to 4,800 rpm. This power curve makes the new car even more responsive over a broader RPM range, with zero-to-60-mph acceleration of 5.6 seconds – 1.1 seconds faster than the previous ML500 model.

Known internally as the M273, the new V8 makes use of the latest advances in lightweight design, with an aluminum block and cylinder heads as well as low-friction silicon-aluminum cylinder liners. In addition to internal exhaust gas recirculation and secondary air injection, the new engine uses two close-coupled catalytic converters with linear oxygen sensors to provide low exhaust emissions.

Variable Intake and Exhaust Valve Timing

Valve timing is automatically adjusted within a range of 40 degrees using electro-hydraulic vane-type adjusters on the end of each camshaft. At part throttle, the adjuster keeps the exhaust valves open as the intake valves are opening, using this valve overlap for internal exhaust gas recirculation to reduce exhaust emissions. Nearing full throttle, the cam adjustment optimizes valve timing for maximum power.

To minimize disturbing air flow through the ports, valve stems are only six millimeters or about 1/4 inch in diameter (most valves have 7 or 8 mm stems), and the valves are angled at 28.5 degrees to optimize the combustion chamber shape.

Tumble Flaps Improve Torque

To help improve engine torque, the V8 engine is equipped with tumble flaps in the intake passages near the combustion chamber. The tumble flaps pivot open under part load, improving combustion by creating additional turbulence around the intake valve and in the combustion chamber. During higher engine loads such as full throttle, the tumble flaps are completely recessed in the wall of the intake manifold.

Two-Stage Intake Manifold Fattens the Torque Curve

While variable valve timing gets a lot of credit for the engine's unusually broad torque curve, a two-stage magnesium intake manifold plays a key role as well. At relatively low engine speeds, a set of flaps in the manifold close off short intake passages, forcing intake air to take a much longer route into the engine. This creates pressure waves that improve torque at lower engine speeds.

Above about 3,500 rpm, the flaps open, and intake air flows the shortest distance to the combustion chambers, helping to make more horsepower, especially at higher engine speeds.

Assembling the V8 from Start to Finish

To assemble the new V8 powerplant, a forged crankshaft with five main bearings is first placed into an all-aluminum engine block that features wide main-bearing saddles and transverse bearing supports that minimize vibration.

The aluminum engine block is cast around Silitek cylinder liners that provide a long-life, low-friction silicon-aluminum running surface for the piston rings. In addition, the block is nearly seven pounds lighter than if it was fitted with conventional sleeves.

Aluminum pistons are pinned onto forged steel connecting rods that are about 20 percent lighter than other comparable engines. The pistons slide into the cylinders, and the connecting rods are clamped around the crankshaft journals. The connecting rod halves feature 'cracked' joining surfaces, in which the initial one-piece forging is hydraulically split so that its irregular fracture creates added strength and durability.

The two cylinder heads are bolted onto the block, and twin camshafts are installed in each head. The intake cams are driven by a double chain from the crankshaft, and small gears on both cams in turn drive the exhaust cams.

Double-wall exhaust piping is used to keep the exhaust air as hot as possible leading down to twin catalytic converters. With the help of secondary air injection, the catalysts promote additional downstream conversion of pollutants into carbon dioxide and water vapor, and two oxygen sensors for each catalyst monitor and help manage the entire process.

ML350 V6 ENGINE

Variable Valve Timing

The ML350 is powered by a 3.5-liter twin-cam V6 engine that produces 268 horsepower and 258 lb.-ft. of torque. Variable intake and exhaust valve timing requires separate camshafts for the intake and exhaust valves, and valve timing is automatically adjusted within a range of 40 degrees using electro-hydraulic vane-type adjusters.

At part throttle, the valve timing adjuster keeps the exhaust valves open as the intake valves are opening, using this valve overlap for internal exhaust gas recircula-tion, reducing exhaust emissions and improving fuel economy. However, approaching full throttle, the camshaft adjustment optimizes valve timing for maximum power.

To minimize interfering with air flow through the ports, valve stems are only six millimeters or about ¼ inch in diameter (most valves have 8 or 10 mm stems), and the valves are angled at 28.5 degrees to optimize the combustion chamber shape.

Improved Fuel Efficiency, More Power

That 258 foot-pounds of torque is on tap all from 2,400 rpm all the way up to 5,000 rpm. In fact, at just 1,500 rpm, the new V6 develops 87 percent of its maximum torque! While the variable valve timing system gets a lot of credit for the engine's unusually broad torque curve, a two-stage intake manifold plays a key role as well.

Two-Stage Intake Manifold Fattens the Torque Curve

The intake manifold is made of a lightweight magnesium alloy. At relatively low engine speeds, a set of flaps in the manifold close off short intake passages, forcing intake air to take a much longer route into the engine. This creates pressure waves that help the intake process and improve torque at lower engine speeds.

Above about 3,500 rpm, the flaps open, and intake air flows the shortest distance to the combustion chambers, helping to generate maximum horsepower, especially at higher speeds.

Tumble Flaps Improve Fuel Efficiency

The ML350 engine is equipped with cleverly designed tumble flaps in the intake passages near the combustion chamber. The tumble flaps pivot open under partial load, improving combustion by creating additional turbulence around the intake valve and in the combustion chamber. During higher engine loads such as full throttle, the tumble flaps are completely recessed in the wall of the intake manifold. While better combustion helps improve engine torque, the primary purpose of the tumble flaps is to further increase fuel economy, and tests show that the tumble flaps indeed boost fuel mileage by about two percent.

Assembling the New Engine from Start to Finish

First, a forged crankshaft with four main bearings is placed into an aluminum engine block that features wide main-bearing saddles and transverse bearing supports that minimize vibration. A balance shaft is installed in the block between the two cylinder banks, about where the camshaft is located on a pushrod-type 'V' engine.

The balance shaft is driven from the crankshaft by a long double chain that loops around one camshaft in each cylinder head and engages the underside of the balance shaft sprocket. This means the balance shaft counter-rotates at crankshaft speed, and its 'lobes' cancel out the inherent imbalance and vibration of a 90-degree V6.

The aluminum engine block is cast around Silitek cylinder liners that provide a long-life, low-friction silicon-aluminum running surface for the piston rings. In addition, the block is nearly seven pounds lighter than one with conventional cylinder sleeves.

Aluminum pistons are pinned onto forged steel connecting rods that are about 20 percent lighter than on comparable engines. The pistons slide into the cylinders, and the connecting rods are clamped around the crankshaft journals.

The two cylinder heads are bolted onto the block, and twin camshafts are installed in each cylinder head. The intake camshafts are driven by a double chain, and gears on the intake cams drive the exhaust camshafts.

Even Downstream Emission Controls are Elegant

Double-wall exhaust piping is used to keep the exhaust air as hot as possible leading to twin catalytic converters located just below the engine. Further downstream, two more catalysts help promote afterburning of carbon monoxide and unburned hydrocarbons. With the help of secondary air injection, the catalysts promote downstream conversion of pollutants into carbon dioxide and water vapor, and two oxygen sensors for each catalyst monitor and help manage the entire process.

ML320 CDI V6 DIESEL ENGINE

New-Architecture V6 Diesel
The ML320 CDI is powered by a new-generation V6 diesel engine with four valves per cylinder, dual overhead camshafts and centrally located piezo fuel injectors. Designed to spray diesel fuel directly into the center of the combustion chamber, each injector is positioned in the aluminum cylinder head about where a spark plug might be found on a four-valve gasoline engine. This layout ensures even dispersion of fuel as its flame front spreads concentrically across the combustion chamber. (In conventional two-valve-per-cylinder diesels in which the injectors cannot be centrally mounted, combustion is uneven, and as a result, there's less power and higher exhaust emissions.)

Closed-Deck Aluminum V6

The all-aluminum V6 diesel is characterized by a 72-degree cylinder angle and 106 millimeter cylinder spacing. Featuring a rigid closed-deck design, the aluminum cylinder block is cast around iron cylinder liners, and a duplex-chain-driven, counter-rotating balance shaft between the two cylinder banks neutralizes the inherent imbalance of a V6, thus ensuring a smooth-running engine.

A forged-steel crankshaft spins in four extra-wide bearings, and pairs of 'split-pin' connecting rod journals are offset by 30 degrees for smoother running. Forged-steel connecting rods are 'cracked' diagonally where they clamp onto the crankshaft, a technique that produces an irregular joint for greater strength, and at the same time, simplifies machining.

Pistons are cast from a special high-temperature alloy and pinned to the connecting rods. Since there is only a slight recess in the cylinder head between each piston and the valves, a combustion chamber is formed by the cavity in the piston crown. This layout has proven to minimize engine-out exhaust emissions in direct-injection engines, and it helps provide the 16.5-to-1 compression ratio necessary to make a diesel engine operate without the external ignition system used on gasoline engines.

DOHC Four-Valve Heads with Central Injectors

The V6 diesel uses two one-piece cylinder heads that are mold-cast from high-temperature aluminum featuring a new heat treatment method. Each cylinder head is fitted with twin overhead camshafts and four valves per cylinder, as well as a centrally mounted injector and ceramic start-up glow plug for each cylinder

The exhaust camshafts are driven by the crankshaft via a double roller chain, and in turn, a pair of helical gears behind the chain sprocket drives the intake cams. The cam lobes operate low-friction roller rocker arms that open the valves. The cams are sandwiched between the top of the cylinder heads and the cast valve covers, so that the heads and the valve covers actually form the camshaft bearings.

Since diesel engines operate without a conventional throttle plate and therefore don't produce much intake vacuum, the camshaft sprocket also drives a vacuum pump for the brake booster. In addition, the right intake cam also operates an oil centrifuge that separates oil from oil-laden crankcase air before the air returns to the intake.

Oil Pump and Cooler

The engine is lubricated by a chain-driven, external gear-type oil pump, which draws oil from the oil pan and pressurizes it throughout the engine. Oil is first fed through a high-volume full-flow oil filter, and is then directed to an integral oil cooler located between the cylinder banks. The oil cooler uses engine coolant to keep oil temperature below 140 degrees Centigrade. The bore for the balance shaft also acts as the main oil galley for the engine, which leads to passages for the crankshaft, piston oil sprayers, cylinder heads and the turbocharger unit.

VNT Turbocharging
While many non-turbo diesel engines have compression ratios over 20:1, Mercedes engineers found that, in conjunction with the CDI engine's exhaust-driven turbocharger, the new engine is most efficient with a compression ratio of 16.5 : 1.

The turbocharger features variable turbine geometry or VNT (Variable Nozzle Turbine), which is integrated with the electronic engine management system. At low engine speed and load, the vane angles are relatively narrow so the turbine speeds up quickly and creates ample boost without noticeable lag. At higher speeds, a steeper vane angle slows the turbine while increasing intake air volume.

Air-to-Air Intercooler

To keep the turbocharged air as dense as possible on its way to the engine, the air flow passes through an air-to-air intercooler – essentially a radiator that cools the intake air. The intercooler system lowers the air temperature by up to 180 F. degrees, ensuring higher air volume and more power.

Electronic Throttle

Diesel engines usually operate most efficiently without any throttle in the intake system, so that fuel delivery alone controls engine load and speed. However, Mercedes engineers found that, at light load, throttling one of the two diesel intake ports on each cylinder creates air turbulence that helps optimize the combustion process and further reduce fuel consumption and exhaust emissions. As a result, the CDI engine makes use of electronic intake port deactivation that's automatically managed by a sophisticated electronic control unit – the same one that determines everything from fuel injection quantity and timing to the vane angle of the VNT turbocharger and the quick-start glow-plug operation. This versatile microprocessor also networks with the seven-speed automatic transmission and the ESP stability control systems.

Common-Rail Direct Injection
The ML320 CDI uses the latest version of the Mercedes-Benz CDI system. To begin the process, a low-pressure electric pump operates at about five bar or 71 pounds per square inch (psi) to draw fuel from the tank and feed it through a fuel filter and water separator to a high-pressure engine-driven fuel pump.

High-Pressure Fuel Pump

A high-pressure pump keeps the electronic fuel injectors supplied with 1600 bar or about 22,720 psi of constant fuel pressure through the common-rail fuel loop. This layout ensures consistent fuel pressure for the common rail, and the amount of fuel used by the engine is determined solely by how long the electronic injectors stay open. In this way, high fuel pressure is always available the instant the injector valve opens, and for as long as it stays open.

Gone are the days of dealing with a mechanical injection pump's gradual fuel pressure build-up for each cylinder, not to mention its pressure drop-off during each cycle – both representing distinct disadvantages, especially at higher engine speeds.

In spite of the high fuel pressure it generates, the engine-driven CDI fuel pump requires less than 20 percent of the peak torque needed to turn a mechanical fuel injection pump. While mechanical injection pumps have to build up pressure for each injector pulse, the CDI pump maintains constant pressure and isn't subject to the shock of such torque spikes. As a result, the CDI pump imposes less stress and potentially less wear on the pump drive.

Ceramic Glow Plugs

In cooler weather, compressing the combustion air in a diesel engine doesn't always make it hot enough to self-ignite fuel when it's injected. As a result, diesel engines have used heating elements called glow plugs for each cylinder as a starting aid. The CDI engine uses ceramic glow plugs, which achieve a glow temperature about 200 degrees C. higher than conventional glow plugs to allow almost instant starting. In addition, the electronically controlled glow plugs can stay on briefly after the engine is started to help regulate idle speed and minimize exhaust emissions.

Piezo-Ceramic Fuel Injectors
Considered technically impossible until the mid-1990s, electronic injectors that remain reliable while they're subjected to approximately 23,000 psi of fuel pressure are the secret of CDI's superiority over earlier injection systems.

However, instead of the usual electro-magnetic solenoid valves, the latest V6 diesel features six piezo-ceramic injector valves. Since piezo crystals actually change shape when electric current is applied, they can be used instead of conventional magnetic elements to provide even faster, more durable injectors. The CDI injectors have eight-hole nozzles that spray a very fine mist of fuel. (concept carz)

Miraculous Pilot Injection
Historically, the diesel combustion process has involved rapid pressure increases and, as a result, more noise than a gasoline engine. Taking advantage of the speed and precision of CDI electronic injection, Mercedes engineers found that igniting a small quantity of fuel a few milliseconds before the main injection pre-heats the combustion chamber and makes pressure and temperature increases more gradual. Smoothing out combustion pressure and temperature spikes softens the usual diesel noise and reduces oxides of nitrogen formation as well. The miracle of pilot injection is only possible because of the speed and flexibility of electronic fuel injection. Pilot injection simply wasn't practical with the relatively slow reaction times of mechanical injection. Now with lightening-fast piezo injectors, up to five injections per stroke can be used instead of the previous three.

An Oxidation Catalyst

Diesel hydrocarbon emissions, primarily in the form of soot, are kept extremely low by the upstream benefits of the engine's centrally located injectors – smooth, even and complete combustion – and two after-treatment devices in the exhaust system. An oxidation catalyst promotes downstream after-burning of any leftover hydrocarbons, while a particulate filter traps soot, even microscopic particles.

Particulate Filter

Made practical by the availability of ultra-low-sulfur diesel fuel, a new particulate filter with a silicon carbide element can separate 99 percent of the soot from diesel exhaust gas. The carbon particles are deposited on the walls of the filter and are periodically cleaned by a filter regeneration process that's not unlike an oven cleaning cycle. The engine control unit monitors exhaust pressure upstream and downstream from the filter, and when there's an appreciable difference, the system briefly provides secondary fuel injection impulses that raise the exhaust temperature to more than 600 degrees C. This high temperature is enough to burn off the carbon particles and form carbon dioxide.

EGR Reduces Nitrogen Oxides
In large part because they usually operate unthrottled with lots of excess air, diesel engines inherently produce less carbon monoxide and carbon dioxide than a gasoline engine. However, because of their high combustion pressure and temperatures, diesels usually make more nitrogen oxides, which contribute to photo-chemical smog. In addition to using pilot injection to minimize oxides of nitrogen, they're further reduced by an exhaust gas recirculation system (EGR), which at partial load diverts a small amount of exhaust gas into the intake stream.

BLÚETEC Is Coming to Mercedes-Benz SÚVs

Currently available in 42 states, the advanced diesel engine in the ML320 CDI is also offered in the 2008 R-Class and GL-Class sport utility vehicles. For the 2009 model, all three Mercedes-Benz SÚVs will get BLÚETEC diesel technology. Currently available only on the E-Class, BLÚETEC includes an innovative urea injection system in the exhaust that makes the diesel engine as clean as a modern gasoline engine. With BLÚETEC, Mercedes-Benz diesel vehicles will be offered in all 50 states.

ML63 AMG ENGINE
AMG Racing Success Spawns High-Power Production Engine
One of the most powerful naturally aspirated production V8s ever, the new 6.3-liter, 503-horsepower engine boasts a wealth of exciting features derived from AMG's highly successful racing efforts. Built almost entirely from a high-strength silicon-aluminum alloy, the new 6.3-liter features four valves per cylinder, variable valve timing, bucket followers (rather than rocker arms) and a variable intake manifold.

AMG is the high-performance division of Mercedes-Benz, and the new engine was a completely autonomous development at AMG. Sharing no parts with Mercedes-Benz V8 engines, the crankcase design, cylinder spacing, bore-stroke ratio, valve train and intake-exhaust manifold design are all unique to the new engine.

Crankcase Bedplate Instead of Main Bearing Caps

For greater strength and reliability, the AMG engine uses a rigid one-piece bedplate at the bottom of the engine block instead of conventional main bearing caps that can distort or loosen at high RPM. The bedplate sandwiches the crankshaft between the two sections of the engine block.

TWAS Twin-Wire-Arc-Sprayed Cylinder Bores

A first for a production engine, the cylinder bores feature a twin-wire-arc-sprayed (TWAS) coating, a new process that results in impressively low friction and running surfaces that are twice as hard as conventional cast-iron cylinders.

Vertical Intake and Exhaust Ports

The AMG engine design includes a two-stage magnesium intake manifold that's part of a vertical intake and exhaust system. In other words, combustion air passing through the engine follows a straight line down through the intake manifold, hemispherical combustion chambers and exhaust passages.

TRANSMISSION

The World's First Seven-Speed Automatic on an SÚV

The M-Class comes with the world's only production seven-speed automatic transmission. (posted on conceptcarz.com) When compared to the previous transmission generation, the seven-speed makes the SÚV both faster and more economical while providing smooth, barely noticeable gearshifts.

Seven gear ratios provide a wider spread of ratios between first gear and top gear and, at the same time, allow smaller increases in engine speed as the vehicle accelerates through the gears. This gives the electronic control unit more flexibility in terms of maximizing fuel economy and making the transmission's reaction time extremely fast.

Skip a Gear When You Need To

Únlike most transmissions, the seven-speed transmission will skip up to three gear ratios if necessary when it downshifts, shifting directly from seventh to fifth, for example, or even sixth to second. This helps the transmission choose the perfect gear ratio for quick acceleration and ensure almost imperceptible shifts in the process.

Lock It Úp for Better Fuel Mileage

The Mercedes-Benz seven-speed uses a refined, proven hydrody­namic torque converter with a special lock-up clutch inside the converter for maximum fuel efficien­cy. The lockup clutch eliminates the usual torque converter 'slippage,' providing the direct connection and fuel efficiency of a manual transmission when the lockup clutch is engaged. In the seven-speed, the lockup clutch engages in all seven gears. (To put that into perspective, many cars lock up the converter only in top gear.) The Mercedes-Benz lock-up clutch is submerged in transmis­sion oil and uses special long-life friction materials.

Where's the Shifter?

One of the most noticeable differences in the interior of the new M-Class is the lack of a shift lever on the center console! Thanks to the latest electronic control technology, a small stalk on the right side of the steering column now serves the purpose.

Shift control is simpler than ever. Lift the stalk up for reverse, push down for drive, and push a button on the end for park. Once underway, pushing either one of the shift buttons on the 'back' of the steering wheel provides Touch Shift manual gear changes.

While all Mercedes automatics feature Touch Shift, the new layout on the M-Class further improves its usability. As on all Touch Shift cars, it isn't necessary to move the shift lever to another gate to make manual gear changes – in fact, the selector lever positions for forward gears are gone. Though gears can be manually selected, computer control prevents downshifts that would cause the engine to over-rev.

Full-Time Four-Wheel Drive

The M-Class uses three conventional 'open' differentials in the front, rear and center of its full-time four-wheel-drive powertrain. The center differential allows the front wheels to go faster than the rear when turning, while the front and rear diffs permit the outside wheels to go faster than the inside ones in turns.

Four-Wheel Traction Control

The Mercedes-Benz M-Class stands apart from many other four-wheel-drive SÚVs by using a four-wheel adaptation of the company's proven electronic traction control to maintain stability and traction on wet or snowy roads. Sometimes referred to as 4ETS, this system senses wheel slip electronically and brakes the slipping wheels, which transfers torque to those tires with the most grip, on virtually any road surface.

Únlike many conventional four-wheel-drive systems, 4ETS automatically provides mobility even when three wheels lose traction. Maneuverability is enhanced, both on and off-road, and in tight steering situations there is no axle 'binding,' which the driver would experience as sluggish steering response and vibration.

The center differential is located in a transfer case, along with a link chain which turns a prop shaft to the front differential. In vehicles equipped with an optional off-road package (coming in later in 2005), a planetary unit in the transfer case provides two selectable gear ranges – 1:1 for on-road use and a 2.93:1 low-range gear reduction for off-road travel.

Únder ideal road and driving conditions, torque distribution is 50 percent front/50 percent rear, so the driver experiences the benefits of full-time four-wheel-drive. In slippery or off-road conditions, the benefit of the full-time system is obvious.

Yet, even on perfectly dry highways, the system makes its presence known by giving the M-Class secure, neutral handling characteristics.

When road conditions turn slippery, or when the driver heads off-road, 4ETS can vary torque transfer front-to-rear and side-to-side to be directed to the wheels with traction. In practice, all available torque can even be transferred to one wheel.

Off-Road Mode

Standard equipment on all M-Class vehicles, an Off-Road button on the center console activates the following features:
· ABS: Available at speeds below 20 mph, the on-off cycling of the anti-lock brake system keeps the brakes engaged more of the time, which purposely locks the wheels and digs into loose surfaces to stop more quickly. Braking distances on loose surfaces are noticeably shorter in the Off-Road mode.
· Traction control: Not unlike the off-road ABS mode, slightly more wheel slip improves traction in gravel or sand.
· Automatic transmission: Shift points are raised so that the M-Class stays in the relevant gear longer.
· Engine: The electronic throttle valve opens more slowly when the accelerator pedal is depressed, allowing vehicle speed to be controlled more easily.

DSR – Cruise Control for Steep Descents

Downhill Speed Regulation is essentially a low-speed cruise control system for steep descents, which is especially helpful in off-road conditions. Activated by another button on the center console, the driver then uses the cruise control stalk to set the speed anywhere between 4 and 12 mph.

The system uses throttle, transmission gearing and automatic braking to help maintain vehicle speed. The descent speed can also be set by using the multi-function steering wheel and a special menu in the central display.

Hill-Start Assist

This new hill-holder technology helps to keep the M-Class from rolling backward on steep uphill grades. If the slope is steep enough, a special inclination sensor allows the system to hold brake pressure when the driver switches from the brake to the gas pedal. Brake pressure is released automatically when the driver accelerates, helping the vehicle to start up steep grades more safely.

The hill-start assist is also active on steep descents, which is often helpful in hilly off-road conditions.

BODY
Úni-Body Platform
The Mercedes engineers who undertook the design of the second-generation M-Class re-examined and analyzed every component – nothing remained sacred. One of the most dramatic departures from the original design is its structural frame.
Instead of a separate 'ladder-type' frame and body shell, the current M-Class features a self-supporting unit body platform. To handle the high load forces involved in off-road driving, the high-stress points between the suspension and body have been redesigned and – above all – made stronger.

Better Torsional Rigidity

One indication of the result is the body's higher torsional rigidity, which is now measured at 2.18 mm per meter – significantly better than its predecessor. As a result, the M-Class boasts improved vibration comfort and excellent handling stability.

'D-Ring' Design Has a Firm Grip on the Body

A continuous 'D-ring' roof structure contributes to the body's outstanding rigidity. This robust connection from the floor, sidewalls and roof frame is also used to attach the rear liftgate. Posted on conceptcarz.com

In comparison to its predecessor, the M-Class body is about 6 inches longer, nearly three inches wider and about ¼ inch lower. The wheelbase is nearly four inches longer, and there's 2 ¼ inches more rear overhang.

Five Times More High-Strength Alloy

While conventional steel continues to dominate the materials mix, the M-Class body uses five times more high-strength alloys than the previous model! In terms of weight, 62 percent of the body panels are now formed from high-strength steel.

Some of these alloys, in particular 'dual-phase' steel, even fall into the very high strength category. The two-phase microstructure of this alloy can withstand very high loads and, as a result, contributes to the strength of the front end and passenger cell.

Low-Stress Welding

The flanges on many of its steel panels are designed so that any tolerances are already compensated for when the sheets are positioned, which allow them to be welded together with less metal stress. This technique also contributes to corrosion protection because it eliminates most of the extra brazed and MAG welding seams, which can be vulnerable to corrosion.

Fully Galvanized Body Panels

Every body panel in the M-Class is zinc-galvanized and organically coated on both sides. The coating also contains rust-preventing zinc pigments.

Many structural areas of the body receive cavity protection, and welding seams are carefully sealed. A six-section plastic undercladding provides protection against stones, water and dirt, eliminating the need for any conventional PVC undercoating. Thick wheel well cladding (1/8-inch thick) also helps protect against stones and gravel.
Chassis

Four-Wheel Independent Suspension
The M-Class features independent front and rear suspension. Four-wheel independent suspension endows the M-Class with class-leading handling, stability and ride comfort – both on and off-road – along with lower noise levels.

Compared to a solid axle, independent suspension reduces unsprung weight by about two-thirds, resulting in both better handling and ride quality. In addition, wheel travel on one side does not change camber of the opposite wheel as with a solid axle.

Double Wishbone Front Suspension

The M-Class front suspension features upper and lower control arms in a double-wishbone configuration. The upper arms are mounted very high in the chassis and are made of high-strength, light-weight forged aluminum alloy, which further reduces unsprung weight, while the lower control arms and steering knuckle are nodular cast iron.

The front suspension uses spring struts with coil springs, gas shocks and large head bearings, and a stabilizer bar attaches to the lower control arms.

A front subframe is attached to the unit body by four large rubber bushings. The subframe carries the engine, transmission, rack and pinion steering gear and the lower control arms, while the upper control arms and shock/spring units connect directly to the M-Class body. The front differential housing is attached by three large noise-insulating rubber mounts.

Four-Link Rear Suspension

Similar to the front, the rear suspension is mounted to a subframe that is isolated from the body by two solid rubber bushings and two hydro-mounts that are filled with a liquid that helps to dampen vibration.

Mercedes engineers developed a four-link rear suspension for the M-Class that consists of the following parts:

1. Forged steel upper rods
2. Sheet steel camber arms
3. Cast iron lower wishbones
4. Tubular steel track rods

Separate shock absorbers are positioned behind the coil springs, and a stabilizer bar completes the picture.

Rack-And-Pinion Steering
The Mercedes M-Class employs a rack-and-pinion steering unit that's mounted ahead of the front wheel center. The hydraulically assisted steering has a variable ratio that operates more directly, or slightly faster, in the center position.

In addition, the M-Class steering is available with a speed-sensitive feature. An electronic valve ensures full power assist at low speeds for easy parking and low-speed turns, and the valve reduces the amount of power assist at higher speeds for improved road feel through the steering.

Serious Brakes

The ML350 and ML320 CDI come with large 13-inch (330 mm) vented front and solid rear disc brakes, while the ML550 is equipped with even larger 13.8-inch (350 mm) vented front discs, with 13-inch vented discs at the rear.

To balance its high speed capability, the high-performance ML63 AMG is fitted with huge vented discs -- 15.4 inches in diameter up front and 14.4 inches in the rear.

Wheels and Tires

Wide, all-season low-profile tires with a relatively wide track underscore the sporty nature of the M-Class. For 2008, the ML350, ML320 CDI and ML550 models are fitted with 8 x 19-inch alloy wheels shod with 255 / 55 R 19 tires. The ML63 AMG comes with 20-inch wheels that are a full 10 inches wide, wearing high performance 295 / 40 R 20 tires.

Height-Adjustable Air Suspension

Developed by Mercedes-Benz, Airmatic air suspension is standard on the ML63 AMG and optional on the other models. Airmatic not only improves M-Class ride comfort, but also provides impressive flexibility by reducing ride height on the highway, increasing it off-road, maintaining vehicle level when loaded and continuously adjusting the suspension damping as road conditions change. The driver can also select three different levels of damping.

Above 77 mph, the AIRMATIC system automatically lowers ride height more than ½ inch (15 mm) for improved handling and stability, as well as less air drag and, as a result, better fuel mileage. When speed falls below 25 mph, the suspension returns to normal height. On rough roads or off-road, a rocker switch on the dash allows the AIRMATIC system to increase vehicle height by more than three inches (80 mm), so that ground clearance is increased to nearly 10 ½ inches – 261 mm.

Adaptive Damping System

AIRMATIC air suspension includes an adaptive damping system that can actually change compression and rebound damping every 0.05 second in response to changing road conditions. If the system senses small body movements, it maintains a comfort mode with relatively soft damping.

With more body movement, the system uses solenoid valves in the shocks to cycle automatically between hard rebound and hard compression modes. A rocker switch on the dash can lock the suspension into a 'sport' mode – hard rebound and hard compression. The switch has three positions, which also allows it to lock in the comfort mode or maintain automatic operation. In summary:

Stage 1 – the 'comfort' setting, with soft compression and rebound damping
Stage 2 – soft rebound and hard compression damping
Stage 3 – hard rebound and soft compression damping
Stage 4 – the 'sport' setting, with hard rebound and compression damping

The AIRMATIC system features air bladders instead of coil springs, and ADS gas shock/air spring struts are used in the front of the M-Class. In the rear, ADS gas shocks are located behind the air springs.

Safety
Crumple-Zone Body Design
Mercedes-Benz safety engineers have designed the unit body platform of the M-Class to take advantage of the latest occupant safety technology. Two longitudinal members of high-strength steel (reinforced with inner steel liners), a front element and two more members above the wheel wells are the key energy-absorbing features of the new front end.

Two crash boxes of high-strength steel bolted to the longitudinal members are designed to absorb most of the impact energy in low-speed frontal collisions. As a result, the crash boxes and a number of other bolt-on components can be replaced less expensively without welding.

At higher speeds, the longitudinal members form a key part of the crumple zone that absorbs more impact energy. In an offset frontal collision, an aluminum bulkhead and several other transverse members are designed to spread the forces across the entire front end. Longitudinal members above the wheel wells serve as a second level of energy absorption in offset frontal collisions.

A high-strength steel subframe that carries the engine, transmission, steering and front suspension is also designed for controlled deformation in a severe frontal collision, and even the wheels play a role. Supported by the strong side walls, the wheels help absorb some of the crash forces.

A High-Strength Passenger Cell

While the front and rear of the M-Class are designed to deform and absorb crash energy, the super-strong passenger cell protects its occupants by maintaining survival space. The floor, roof pillars, longitudinal members and side walls frame this rigid safety zone.

The transmission tunnel is formed of thick steel and serves as the backbone of the floor structure. Transverse cross members connect to the tunnel and provide high lateral strength in a side impact, as well as a solid mounting point for the seats. In addition, diagonal members extend from the front bulkhead to the B-pillars to further strengthen the floor.

External side panels and multi-piece interior side panels help to shape and strengthen the roof pillars, roof frame and side members. As an aside, sound-absorbing foam contributes to impressively low noise in the M-Class, and 34 such foam sections are incorporated just in the two side walls.

Rear Crumple Zones, Too

The rear longitudinal members of the M-Class are made of continuous closed box sections with tapered thickness for low weight and maximum strength in a rear collision. The fuel tank is located in a protected area in front of the rear wheels.

Like the front, the rear also features bolt-on steel crash boxes and an aluminum cross-member that absorb impact energy in low-speed collisions, which can be replaced in a relatively simple and lower-cost procedure.

Seat Belts, Belt Tensioners and Belt-Force Limiters

The M-Class is fitted with three-point, inertia-reel seat belts for all five seating positions, as well as electronically controlled belt tensioners and belt-force limiters for the four outboard seats. In a collision that exceeds the deployment threshold, the tensioners take up seat belt slack to increase the its effectiveness by allowing restraining contact between the belt and occupant earlier in the collision sequence. Later in the sequence, belt force limiters can somewhat limit the restraining force of the seat belt against the occupant, reducing the risk of chest and shoulder injuries.

Two-Stage Front Air Bags

Two-stage front air bags for the driver and front passenger feature two inflation rates, depending on the severity of impact and other factors such as the weight category of the front seat occupant. For example, if sensors detect a front-end impact that exceeds the activation threshold for an average occupant, only one chamber of the gas generator is deployed. In a more serious frontal collision, a second chamber is deployed 5 to 15 milliseconds later to increase the inflation rate of the air bag.

Active Front Head Restraints

Another example of Mercedes-Benz leadership in automotive safety, the 2008 M-Class is equipped with active front head restraints. In the event of a rear collision exceeding the system's deployment threshold, the front head restraints move forward more than 1¾ inches (44 mm) and upward by more than an inch (30 mm), helping to support the head and reduce the likelihood of whiplash injuries.

Side Impact Protection

The M-Class comes with standard window curtain air bags – devices that can help cushion front and rear occupants when their heads hit the side windows or roof pillars in a side collision. In addition, the air-filled cushion can block glass splinters or other objects that could cause injury in a side impact or rollover. Over six feet long, 14 inches in height and about two inches thick when inflated, a window curtain air bag on each side of the car can deploy in about 25 milliseconds from the ceiling and extends across both front and rear side windows.

Many severe and often fatal head injuries in side collisions are due to either an occupant's head striking the interior or the whiplash movement of the head. Crash tests with the window curtain air bag indicate about a 90 percent reduction in the forces likely to cause head injuries.

The M-Class also comes standard with door-mounted side air bags for the front and rear seats that protect the torso and work in conjunction with window curtain air bags.

A Highly Advanced Sensor System

A highly advanced sensor system gives the restraint system excellent reflexes. Two sensors in the nose of the M-Class (on the radiator cross member) provide initial collision data, and can deploy the belt tensioners before the primary sensor in the cabin could react. These upfront sensors can also provide data to the system's central processing unit earlier in the collision sequence, helping it determine whether or not both stages of the front air bags should deploy.

Satellite sensors in the lateral cross members under the seats work together with the central crash sensor to deploy the side air bags in the event of an actual collision that exceeds the deployment threshold.

Sensors in the front passenger seat are used to determine the passenger's weight category, and the inflation rate of the air bag deployment is varied accordingly.

Rollover Sensor

The M-Class is also equipped with a rollover sensor, which can recognize this type of accident and relay the information to the restraint systems' central control. If the sensor detects a rollover, the central control unit activates the belt tensioners and curtain air bags.

Tire Pressure Monitoring

Mercedes-Benz inventions such as ABS anti-lock brakes, ASR traction control ESP stability control and Brake Assist are standard on all Mercedes passenger vehicles, including the new M-Class. However, the 2008 sport utility has a new feature that makes clever use of existing wheel speed sensors for ABS and ESP.

Since an under-inflated tire is smaller and rolls slightly faster to keep up with the other three, the system uses wheel speed signals to identify under-inflated tires and alert the driver. In effect, the ESP system not only helps to keep the car safely on course but now also keeps an eye on tire pressure.

Standard Equipment – All M-Class Models
Performance
• Úni-body design

• 3.5-liter, 268-hp, 258 lbs./ft. torque V6 gas engine or 3.0-liter, 215-hp 398 lbs./ft. torque V6 diesel

• Driver-adaptive electronically controlled seven-speed automatic transmission

• Full-time four-wheel-drive with 4-Wheel Electronic Traction System (4ETS)

• 4-wheel independent suspension

• 4-wheel 13-inch disc brakes with 4-channel Anti-Lock Braking System (ABS)

• 19-inch aluminum alloy wheels

• 255 / 55 R19 all-season radial tires

Safety and Security

• Safety cell and crumple zone body

• Driver and passenger two-stage adaptive front air bags

• Door-mounted side air bags in front and rear

• Central locking system

• Automatic anti-theft alarm

• Illuminated entry system

Exterior

• Halogen headlamps with high-impact polycarbonate lenses

• Chrome door handles, tailgate trim and side molding

• Dual heated power side-view mirrors

• Rear-window defroster

• Single-lift tailgate/door

• Rear wiper

• Power Glass Sunroof

Interior

• Multi-function steering wheel (and dash display)

• Second-generation modular COMAND system (single CD slot and aux audio input)

• Power front seats

• Power windows on front and rear doors with express down and up (on door panel)

• Easy fold-down rear seat (60:40 split for passenger and cargo versatility)

• Air conditioning with dust filter

• Cruise control

• 4-speaker, 80-Watt audio system with AM/FM/Weatherband CD stereo and integrated CD controls

• Factory pre-wiring for optional CD changer and integrated cellular telephone

• Full instrumentation including speedometer, tachometer, fuel and coolant temperature gauges, electronic digital odometer, resettable trip odometer and quartz clock

• Delayed-shutoff front courtesy lamps

• Four reading lights

• Rear seat and cargo-area courtesy lights

• Illuminated visor vanity mirrors

• Front center armrest with two-level storage

• Two front console cupholders

• Dual rear cupholders

• Storage pockets in dash, doors and front of console

• Retractable cargo cover

Additional ML550 Standard Equipment

• 382-horsepower 5.5-liter DOHC V8 Engine

• 13.8-inch front brake discs

• Heated Front Seats

• Burl walnut interior trim

• Running Boards

• Rain sensor

Additional ML63 AMG Standard Equipment

• 503-hp 6.3-liter AMG-designed V8 Engine

• 15.4-inch front brake discs, 14.4-inch rear

• Airmatic air suspension with ADS shocks & speed-sensitive parameter steering

• 20-inch AMG alloy wheels with 295 / 40 R 20 tires

• AMG Aerodynamic Bodywork

• AMG Nappa Leather interior and power/memory sport seats

• Burl Walnut interior trim

• P3 Package

• CD Changer

Other Options

• Height-Adjustable AIRMATIC Air Suspension (with ADS Active Damping System)

• Bi-Xenon Curve Illuminating Headlights (with corner illuminating front fog lights)

• harman/kardon Logic 7 audio system

• Six disk CD changer

• Cargo Management System

• Rear View Camera

• Rear Seat Entertainment System

• Keyless-Go

• Parktronic

• Satellite Radio

• Power Liftgate

• DVD Navigation

• Memory Seats and Mirrors

• Heated Rear Seats and Steering Wheel

• Trailer Hitch

• CD changer

• Integrated Cell Phone and Voice Recognition System

• Interior Ambient Lighting Package

Source - Mercedes-Benz