Adding to the exceptionally comprehensive look at the Europe-bound Mercedes GLK we brought you earlier this month, Mercedes-Benz USA today has unveiled an equally extensive look at the variant that will make its way to the states:  The 2010 Mercedes GLK350 4MATIC. Nearly every facet of the model is covered, ranging from its design to its various technical and safety features, so if you've been contemplating whether or not the new SUV is worthy of you hard-earned income, grab a cup of coffee, sit back and get ready for a gargantuan portion of pure, unadulterated GLK-themed goodness.

Enjoy ladies and gentlemen.



The 2010 Mercedes-Benz GLK350 4MATIC

Introduction.................................................................................... Newest Member of the Mercedes-Benz SUV Family
Exterior Design............................................................................... Taut Lines and Rounded Surface
Interior............................................................................................. What’s Looks Good, Feels Good
V6 Engine........................................................................................ Four-Valve Engine Technology
Seven-Speed Transmission......................................................... Skip a Gear When You Need To
4MATIC Four-Wheel Drive............................................................ The Latest 4MATIC System
Chassis........................................................................................... An Ultra-High-Strength Steel Unit Body
Safety............................................................................................. Seat Belts, Tensioners and Belt Force Limiters
Conclusion...................................................................................

Introduction

Newest Member of the Mercedes-Benz SUV Family
On the heels of the widely publicized Vision GLK concept vehicle that made its debut in January 2008 at the North American International Auto Show, a production GLK makes its debut in early 2009 as a 2010 model. The mid-size GLK represents the newest member of a highly successful Mercedes-Benz SUV family that includes the full-size M-Class, which spurred the trend toward more car-like SUVs, as well as the larger GL-Class, the crossover R-Class and the rough-and-tough G-Class. Already considered the broadest luxury car lineup in the auto industry, Mercedes-Benz can boast 14 model classes with the GLK, which arrives in the U.S. as a V6-powered GLK350 model with a choice of 4MATIC all-wheel drive or, later, rear-wheel drive.

Just the Right Size for Today’s Family
At first glance, the new GLK appears to be a smaller version of the GL, but a closer look reveals a modern interpretation of the iconic G-Class. In sharp contrast to the relatively soft forms of other similar-sized vehicles, the striking, angular nose of the GLK sets it apart from the competition. From its projection lights and steeply-raked windshield to the integrated rear spoiler on its tightly styled roof section, the bullish shape of the new GLK suggests power and agility. At the same time, the new GLK is just the right size for today’s family, whether it’s parking in town while running errands or making a cross-country trip.

One of the Most Fuel-Efficient Mercedes-Benz Vehicles Ever
The new sport utility is destined to be one of the most fuel-efficient Mercedes-Benz vehicles ever produced. Smaller and lighter than its well-known SUV siblings, the GLK features a fuel-sipping 3.5-liter V6 engine, a sophisticated seven-speed automatic transmission and available 4MATIC full-time four-wheel-drive.

Compared to other Mercedes-Benz SUVs, the GLK could prove to be the most agile member of the family. Like nearly all Mercedes passenger vehicles, the new GLK features four-wheel independent suspension worthy of a sports car. With respectable ground clearance for off-road driving, available running boards, roof rack and skid plates emphasize the versatile SUV character of the new GLK.

Impressive Interior Design and Safety Technology
Inside, the new SUV has all the impressive design ambiance and safety technology of Mercedes-Benz cars. Standard equipment includes front, side and window air bags. Much as the latest C-Class sedan has brought a new level of sporty driving and ride comfort to the sedan world, the new GLK sport utility will bring a new combination of agility and comfort to the SUV market. The GLK also broadens and extends the Mercedes-Benz sport utility line with cutting-edge engine and four-wheel-drive technology packaged in a stylish, fuel-efficient vehicle that’s the perfect size for today’s busy family.

The GLK Buyer and Its Competition
The new GLK should appeal to younger families and a broad range of buyers looking for good fuel economy in a luxury sport utility vehicle. The GLK competes with Japanese crossover SUVs that include the Acura RDX, the Infiniti EX and the Lexus RX as well as European models such as the BMW X3 and the Land Rover LR2.

Exterior Design

The new GLK is the first Mercedes-Benz in the small sport-utility category. More than 10 inches shorter than the M-Class, the GLK is also a few inches shorter than its primary competition – the Acura RDX, Infiniti EX and Lexus RX. Classed as a mid-size SUV, the Mercedes-Benz GLK is just the right size for today’s family, whether they’re visiting relatives halfway across the U.S. or running errands across town.

Taut Lines and Rounded Surfaces
The look of the GLK is strikingly expressive. Although the new SUV bears an obvious family resemblance to its larger GL sibling, the GLK is more a contemporary reinterpretation of the rough-and-tough G-Class. The angular hood of the GLK differentiates it from the soft, rounded lines of other similar-sized vehicles, and yet the new GLK boasts wind-cheating, fuel-saving aerodynamics. With a drag coefficient of 0.35, the GLK requires little power to slip through the air, and should prove to be one of the most fuel-efficient Mercedes-Benz vehicles ever.

Like other recent Mercedes-Benz vehicles, the design language of the new GLK features an interplay between taut lines and broad, rounded surfaces. Its two-box proportions includes short overhangs (for steeper approach and departure angles), while a sharp-edged nose, steeply raked windshield and sweeping roof lines make it clear that the new GLK is tough, practical sport utility vehicle. Its proportionately large wheels and tires complete the picture, also helping to increase ground clearance and off-road capability.

Numerous Nice Touches
The U.S. version of the GLK comes with a two-slat grill and body-color side skirts, as well as a number of finishing touches in chrome or stainless steel – fog light surrounds, door trim strips, shoulder line trim, tailpipes, rear apron trim, and the trunk sill. Underscoring the high-tech character of the new SUV, projector beam headlights are mounted under clear lenses in translucent cylinders reminiscent of high-quality camera lenses.

Interior

The exterior styling of the new GLK carries through to the complementary aesthetics of the interior. First impressions usually focus on its broad interior width and the use of high-quality materials with contemporary surface treatment.

What Looks Good, Feels Good
To minimize glare, the upper dashboard is black, while the lower section around the glove box, center console and knee protection wears the dominant interior color. Air vents and controls blend into the upper dash, as does the new instrument panel.

In large part, the high-quality appearance of the interior is the result of a special production process that leaves a seamless surface with no lines or joints. Robots spray a foamed surface skin onto the dash backing; this poly-urethane skin is soft to the touch and can be thicker or thinner as needed.

To minimize resonance and vibration, an aluminum cross member supports the dashboard, and the glove box, front passenger air bag and center console are attached to the cross member. Lighter than a comparable steel one, this cross member is bolted to the A-pillars, giving them added strength in the process. A large glove box comes with a power socket and a plug for a MP3 player which connects to the car’s audio system.

Blending into the lines of the dash and the tunnel console, the center console holds panels for the audio system and climate control, along with switches for other equipment such as heated seats. The shift lever and central controller are located on the tunnel console as well as an arm rest that’s contoured to serve as a helpful hand rest when operating the new electronic controller.

A High-Performance Instrument Cluster
The instrument cluster features three analog gauges that show engine speed, road speed, fuel level and coolant temperature. A 4.5-inch display in the center of the speedometer is linked to a 12-button multi-function steering wheel that can call up a variety of helpful information such as odometer, range, oil level, distance, time traveled and average speed and mpg. It can also display phone and audio system information – radio station, CD track or MP3 playlist. If the car is equipped with the optional COMAND navigation system, this display will also show next-turn directions or phone book numbers.

Electronic Controller Instead of Scores of Buttons
Similar to the popular system launched on the top-of-the-line S-Class sedan and CL coupe, an electronic controller on the lower console works like a computer mouse to provide easy, quick operation of many functions that used to require scores of separate buttons and switches. By turning and pressing the aluminum controller, menus and sub-menus on the center-console display are displayed and selected for the audio system as well as the optional navigation system and integrated phone. The controller is also linked to the rocker switches on the multifunction steering wheel.

Concert-Hall Audio
Standard equipment in the new GLK is an 80-watt Audio 20 system. In addition to its eight speakers, the Audio 20 includes a single CD slot, telephone keypad, a Universal Media Interface plug in the glove box and Bluetooth connectivity. Optionally available is a harman/kardon LOGIC7 Dolby Digital/DTS 5.1 discrete multi-channel, surround-sound system, delivering 450 watts of true studio sound experience. The LOGIC7 system comes with 12 speakers, including two surround-sound speakers and a sub-woofer.

As part of the Multimedia package, the new GLK includes a MusicRegister feature, which enables CD "ripping" (saving) to a four-gigabyte hard drive that can store up to 1,000 tracks from a CD. A Gracenote database automatically identifies each track with its title, artist, album name and other information. The audio system can also play tracks stored on a DVD or PC memory card.

COMAND Navigation
The optional COMAND navigation system features a seven-inch color TFT display screen in the center console (the standard Audio 20 system has a five-inch display) and a hard drive with map data covering all of North America. In addition to the high-resolution map display at the top of the center console, next-turn navigation instructions can also be shown in the instrument cluster central display.

Bluetooth Integrated Phones
Bluetooth-enabled phones connect wirelessly to a standard hands-free system, which facilitates safer cell phone use while driving. The audio system is automatically muted during calls, and phone conversations make use of the audio speakers and two microphones built into the rear-view mirror. Call lists and phone address books can be shown on the standard central dash display or the optional COMAND screen.

V6 Engine

Four-Valve Engine Technology
The new GLK is powered by a high-tech Mercedes-Benz V6 that’s characterized by four valves per cylinder and variable valve timing. In the 1990s, Mercedes-Benz engine technology used three valves per cylinder, in which a single exhaust valve kept exhaust temperature high and emissions low, but the current engine family incorporates new ways to minimize emissions, allowing the use of higher-flow four-valve architecture.

The new GLK350 features a 268-horsepower 3.5-liter V6 with 258 pound-feet of torque. Maximum torque is available from 2,700 rpm all the way up to 5,000 rpm. In fact, at just 1,500 rpm, the V6 develops 87 percent of its maximum torque.

Variable Valve Timing
Variable intake and exhaust valve timing requires separate camshafts for the intake and exhaust valves, so the V6 powerplant in the new GLK uses double-overhead camshaft technology. 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 recirculation, reducing exhaust emissions and improving fuel economy. However, approaching full throttle, the camshaft adjustment optimizes valve timing for maximum power.

To minimize disturbing 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.

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 intake manifold made of a lightweight magnesium alloy 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 and creating pressure waves that help the intake process and improve torque at lower engine speeds. Above about 3,500 rpm, the flaps open electronically, 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 GLK 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. Better combustion helps improve engine torque, but 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 then installed in the block between the two cylinder banks, about where the camshaft is located on a pushrod-type V6 or V8 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 vibration created by the inherent imbalance of the 90-degree V6.

When the cylinder block is cast, molten aluminum is poured around iron cylinder sleeves, melting the outer surface of the iron sleeve and bonding it to the aluminum block. 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 cams.

Even Downstream Emission Controls are Elegant
To keep exhaust air as hot as possible leading to the catalysts, double-wall stainless-steel piping is used throughout the exhaust system. Two catalytic converters – one on each bank of the V6 engine – promote downstream conversion of pollutants into carbon dioxide and water vapor with the help of secondary air injection. Two oxygen sensors for each catalyst monitor and help manage the entire emissions-reducing process.

Each GLK is also equipped with five mufflers – two up front, one in the center and two in the rear. Although the new GLK has a true dual exhaust system, the center muffler is common to both pipes as a means to smooth the exhaust pulsations on both sides and reduce exhaust noise.


Seven-Speed Transmission

The new GLK comes with the exclusive Mercedes-Benz seven-speed automatic transmission as standard equipment. When compared to other automatic transmissions, the seven-speed provides better acceleration and fuel economy as well as smoother gearshifts. Seven gear ratios allows for a wider spread of ratios between first gear and top gear and, at the same time, smaller increases in engine speed as the car accelerates through the gears. This gives the engine’s 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
Unlike 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 right gear ratio for quick acceleration, with smooth, almost imperceptible shifts
in the process.

Lock It Up for Better Fuel Mileage
The Mercedes-Benz seven-speed uses a refined, proven hydrody namic torque converter with a special lock-up clutch inside the converter for maximum fuel efficien cy. Submerged in transmis sion oil and using special long-life friction materials, 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. Unlike many other vehicles, the Mercedes-Benz lock-up clutch engages in all seven gears.

Touch Shift – Just Like It Says
Touch Shift allows the driver to manually select all forward speeds by pushing the gear lever slightly left or right to downshift or upshift while in the “Drive” selector position. In other words, it’s not necessary to move the lever to another gate to make manual gear changes, and an in-dash gear indicator shows the selected gear.

Though all forward speeds can be selected, computer control prevents downshifts that would cause the engine to over-rev. Once the driver has used Touch Shift to manually select a gear, holding the lever to the right returns it to fully automatic Drive mode, and the in-dash gear indicator will then display “D.”

Doing It Automatically
When not shifting manually, Mercedes automatic transmissions not only adapt to changes in road grade (delaying upshifts on ascents for climbing power and hastening downshifts on descents for engine braking), but also to an individual’s driving style. The transmission computer adjusts shifting logic for leisurely driving with smooth upshifts for the best fuel efficiency.

By comparing road speed changes and load (throttle opening), the transmission computer can discern uphill and downhill grades and adjust shifting as a result. It avoids back-and-forth shifts between two gears on a long incline, and delays upshifts on descents (for engine braking), as a driver is likely to do with a manual transmission. A driver who requires frequent highway merging will find the transmission holds each gear longer for quicker acceleration.

A button next to the gear selector allows the driver to select a Sport or Comfort shift mode. The Comfort setting is used for normal driving, which involves smooth, soft shifts and relatively low-speed shift points. When the Sport mode is selected, shift points occur at higher engine speeds, and shifts are faster and crisper.


4MATIC Full-Time Four-Wheel Drive

The new GLK is available with a choice of rear-wheel drive or the highly successful Mercedes-Benz 4MATIC full-time four-wheel- drive system. The 4MATIC system features a center differential that can vary front-to-rear torque distribution for great on-road handling, not to mention stellar traction. In addition, the system includes innovative four-wheel electronic traction control that keeps the vehicle going even if only one wheel has traction.

The Latest 4MATIC System
The 4MATIC full-time all-wheel-drive system in the new GLK made its debut on the new-generation S-Class sedan. This totally redesigned system is integrated into the seven-speed automatic transmission, fits right into the standard body and utilizes the existing front suspension – gone are the special suspension parts and wider transmission tunnel that were necessary on earlier 4MATIC systems. The extra gears and shafts that drive the front wheels now weigh only 145 pounds more than the rear-wheel-drive model. Beginning from the right side of the transmission tail section, a driveshaft powers a front final drive and differential unit just to the right of the engine oil pan. The axle shaft for the left front wheel passes through a tube inside the engine oil pan.

Optimal Fuel Efficiency
Fuel efficiency has been optimized, due to a number of innovative measures that minimize the energy needed to turn the extra all-wheel-drive shafts and gears. In particular, only two gears now power the front driveshaft (instead of the previous three), and the direction of rotation is cleverly corrected in the front final drive without additional gears. Recessing the universal joint for the front driveshaft into the transmission output gear also saved space, helping to fit the entire drive system into the standard body shell.

Multi-Plate Diff Clutch For Even Better Traction
The 4MATIC system in the new GLK also comes with a multi-plate clutch tucked into the center differential that provides the extra traction benefits of a limited-slip diff while complementing the four-wheel traction-control system. Sometimes called a “breakaway” clutch, the multi-plate unit helps provide power equally to the front and rear wheels when driving straight ahead, but still allows the front wheels to rotate faster in turns. In a sense, the clutch is a proactive traction aid, while the four-wheel traction control reacts after wheel slippage is sensed.

A Full Century of 4WD Experience
Mercedes-Benz has been building four-wheel-drive commercial vehicles since 1907 – more than 100 years of experience with all-wheel drive. The 4MATIC all-wheel-drive system made its world debut at the Frankfurt Motor Show in 1985, and Mercedes-Benz launched 4MATIC-equipped passenger cars in the U.S. market for the 1989 model year. The full-time 4MATIC system made its debut on the 1998 E-Class sedan and wagon as well as on the M-Class sport utility.

A Trend in the Luxury Market
As modern all-wheel-drive systems become even more refined, they are becoming increasingly popular, especially in the luxury market. With negligible weight and fuel-efficiency tradeoffs, full-time four-wheel-drive systems provide year-round traction and stability benefits on both wet and dry roads. Overall, Mercedes-Benz has sold more than 1.2 million 4MATIC cars and sport utilities, and in Europe, the all-wheel-drive segment of the high luxury market has increased 50 percent over the past three years.

Chassis

An Ultra-High-Strength Steel Unibody
High-strength steel minimizes weight while providing the greatest possible structural strength, and the 2010 GLK sport utility uses generous amounts of high-strength steel in its unibody. The new GLK also makes use of the new RobScan joining process, the latest in laser welding technology. RobScan enables high work speed combined with narrow welding seams.

Aluminum and Plastic Where It Counts
Other lightweight materials are used where they offer the most advantages. For example, several structural members are made of aluminum, while the fuel tank and spare tire well are formed of high-strength plastic. Lastly, the use of special adhesives contributes to the strength of the body shell by creating a strong bond between the steel flanges and supplementing conventional processes such as laser/spot welding, which helps to increase load resistance and the transfer of forces, especially in safety related areas.

Lightweight, Energy-Absorbing Front Suspension
The GLK front suspension combines two separate lower links with a coil spring strut, along with a twin-tube gas shock and a stabilizer bar. Rather than one large control arm like a conventional MacPherson strut, the two forged-aluminum lower links help provide better impact absorption in the case of a frontal impact. Their low mass also contributes to more precisely-tuned wheel control and damping. In addition, sensitivity to wheel imbalance or brake fluctuations is minimized.

The top of the strut is connected to the body by a triple-path head bearing, in which coil spring forces are transmitted directly to the body, but damping forces (via the shock absorber piston rod) go through a rubber bushing that turns with the bearing during steering. Forces that exceed suspension travel (a pothole or curb, for example) pass through a buffer stop directly to the body. The front suspension links are mounted to a sub-frame of high-strength steel that also carries the engine and transmission as well as the rack-and-pinion steering unit, which is mounted in front of the wheel center.

Multi-Link Rear Suspension
The proven Mercedes-Benz five-link independent rear suspension has been updated for the GLK. Mercedes engineers have redesigned its parts to minimize unsprung weight and optimize strength. Furthermore, suspension engineers revised all the elastokinematics – wheel deflection that’s desirable under extreme load – to ensure optimum response to vibration and enhance the sedan’s predictability while driven hard. A newly designed rear sub-frame, also of high-strength steel, holds the rear final drive and suspension links.

Agility Control Damping
Agility Control technology provides the benefits of both soft and stiff shock absorbers. Each shock absorber in the GLK is fitted with a hydraulic by-pass piston that acts like a very soft shock absorber to effectively dampen road noise and tire vibration. However, the by-pass piston is inactive during normal shock absorber operation, which preserves the outstanding steering and handling response of a stiffer shock absorber.

Extra Braking Power in Reserve
As on every Mercedes-Benz passenger vehicle, the new GLK features four-wheel disc brakes with a standard anti-lock braking system (ABS) – a Mercedes-Benz innovation first produced in 1978. The brake pedal operates an aluminum master cylinder, and a tandem brake booster (also aluminum) uses two eight-inch diaphragms to amplify the pedal power. Floating calipers (twin-piston up front and single-piston in the rear) squeeze the brake pads against large vented brake discs – 13 inches in front and 11.8 inches at the rear.

Standard 19-Inch Wheels and Tires
The GLK rides on 7.5-inch-wide, 19-inch-diameter ten-spoke alloy wheels that wear 235 / 50 HR 19 all-season tires. Optional 20-inch seven-spoke wheels feature staggered width – 8.5 inches wide up front and 9.5 inches in the rear, with 235 / 40 R 20 tires in front and 255 / 40 R 20 at the rear.


Safety

The renowned safety of Mercedes-Benz automobiles has been based on real-life experience for decades. Careful analysis of actual traffic conditions and accident histories help steer new technical developments. In addition to meeting government standards, the technical safety aspects of the new GLK also reflect in-house Mercedes-Benz accident research. The GLK is designed for the greatest possible impact safety, based on Mercedes’ own stringent guidelines that date all the way back to 1951, when the company patented its energy-absorbing car body with front and rear crumple zones.

Pedestrian Safety
The design of the new GLK even considers the possibility of a pedestrian collision. Its relatively tall front hood allowed the design of a vertical crumple zone above the engine that can help cushion a pedestrian’s head and upper body in the event of a collision. The rigidity of the front hood and the position of components under it – reservoirs, control units and the wiper assembly – have been designed with pedestrian safety in mind.

Seat Belts, Tensioners and Belt Force Limiters
All five seating positions in the new GLK are fitted with three‑point inertia‑reel seat belts and electronically controlled belt tensioners. In a collision, the tensioners take up seat belt slack at lightning speed, anchoring occupants to their seats. As a result, they decelerate with the vehicle earlier, so forces are reduced. Then, as crash forces build, belt force limiters on the outer four seats relax the belts slightly, reducing the risk of chest and shoulder injuries. In the two front seats, adaptive belt force limiters allow belt forces to relax more, to take full advantage of the “ride-down” protection of the two front air bags.

Two-Stage Front Air Bags
Two-stage front air bags for driver and passenger deploy based on the severity of impact. If sensors detect a minor front-end impact, only one chamber of the gas generator is deployed, so the bag is not filled as fully or as quickly as it is in a severe front impact. In a more severe collision, the second chamber is deployed 5 to 15 milliseconds later.

A sensor mat in the front passenger seat determines if someone is in the seat and classifies their weight, which helps determine how fast to deploy the front passenger air bag. If the seat is not occupied, the sensor will deactivate the front air bag, side air bag and the seatbelt tensioner (a measure designed to reduce accident repair costs). Signals from the seat belt latches help determine how many other passengers are in the car, and where they are sitting.

Active Front Head Restraints
In the event of a rear collision that exceeds the system’s deployment threshold, active front head restraints move forward more than 1¾ inches (44 mm) and upward by about an inch (24 mm), helping to support the head and reduce the likelihood of whiplash injuries.

Curtain and Side Air Bags, Too
Another Mercedes-Benz innovation is standard-equipment side curtain air bags. Akin to an air mattress, a row of air chambers in each side curtain air bag spans the full distance of the side windows from front roof pillar to rear roof pillar. In the event of a side crash, they deploy between the occupants and the door, helping primarily to reduce forces acting on the neck and head. While the curtain air bags reduce head and neck injuries, side air bags integrated into the seatbacks help protect the chest, resulting in one air bag complementing the other.

Structural Side Impact Protection
In the floor of the new GLK, reinforced rocker panels transfer impact forces to two strong side members in each foot well, under the front seats and to a full-width cross member under the rear seat. The transmission and driveshaft tunnel reinforcements also improve the transfer of forces between the front seats.

At medium height, the doors themselves are stiffened with several lateral reinforcements and extremely strong door hinges. An extruded aluminum cross member under the dashboard provides lateral structure as well as the seat frames and backrests themselves. Finally, the GLK roof minimizes intrusion, thanks to three-shell construction – or concentric posts – through the full height of all four roof pillars. The roof frame itself is also made of this three-shell construction. All this front and side impact protection is repeated in the rear, even in an offset rear-end impact at high speed.

Five Elements of Safety
Safety encompasses far more than surviving impact. As an overall concept, good vehicle safety integrates the prevention of accidents via quick response to driver input, electronic assistance (ABS, ESP Stability Program, Brake Assist), soft and progressive impact absorption, controlling the body movement of passengers due to impact, and quick emergency response to passengers in severe impacts. The 2010 GLK fulfills each of these five elements in this increasing scale of safety concerns:

1. Actively Avoiding Impact
The best type of crash is one a driver can avoid altogether. To that end, the new GLK uses outstanding suspension and brake design to yield outstanding agility in emergency maneuvers. Also, through a variety of sensors, a triangle in the middle of the instrument panel warns the driver when the car has reached the limits of adhesion and handling.

2. Electronic Assistance to Avoid Impact
Should emergency driver input cause a potential skid or spin, three forms of dynamic driving assistance – ABS anti-lock braking, ESP stability control and Brake Assist – help restore control of the vehicle and perform the maneuver asked by the driver.

3. Impact Absorption
If an impact is unavoidable, the vehicle should protect its occupants, and – Mercedes-Benz believes – protect occupants of another vehicle by absorbing impact energy in a progressive manner. The first instant of impact should start the deformation process, and in a fraction of a second, resistance should increase, ending the event with the passenger cell structure intact to best provide passenger protection. If impact energy is viewed on a graph, impact absorption appears as a curved line, showing that the vehicle’s front and rear crumple zones “catch” the impact as softly as possible within the space provided. Also, the GLK front suspension helps absorb frontal impact energy by using two separate, low-mass lower control arms and a steering rack mounted to a predictably-deformable sub-frame.

Deformation is engineered into several stages as well. Low-speed impact energy is absorbed by foam elements in the bumpers, protecting metal panels aft of the bumpers. Higher impact energy is absorbed by a front module and two crash boxes that use high-strength, dual-phase steel. These crash boxes not only protect the passengers and the safety cell of the vehicle, they also help minimize the cost of minor crash repair. With even higher impact energy, the side members in the front structure begin absorbing impact, distributing load to four different zones:

a - the front module’s cross member, which transfers the impact forces of an offset crash to the side not directly involved

b - the side members that extend far to the front

c - the strong sectional panels above the wheel wells

d - the front wheels themselves, which then contact special impact-absorbing structures ahead of the rocker panels, loading the body’s side structure and helping to spread forces over a wide area.

4. Controlling Passenger Movement
Occurring simultaneously with the vehicle’s crumple zones absorbing energy, the GLK restraint systems for each occupant keep passengers from moving out of position. Properly-latched seat belts, seat belt pretensioners and belt force limiters go a long way to achieving this in the GLK, while a complement of two front, side, and two full-interior-length side curtain air bags help prevent injury to head, neck and arms.

5. Emergency Response
Passenger safety is not over once the collision stops. In the case of a severe collision, emergency response is vital. To address this last portion of the safety picture, the GLK can be equipped with the innovative Mercedes-Benz Tele Aid system. Tele Aid is activated immediately when any one of the air bags or belt tensioners deploy, generating a direct call on a crash-secure cellular line and redundant antennae. The response specialist at the other end has instant access to vehicle location, so that if emergency response is indeed needed, it can be summoned immediately, with exact location, plus full information on the car model and color for quick recognition by emergency services.

Repair-Friendly Crash Boxes Help Reduce Cost
Five polypropylene impact absorbers are located in front of the bending cross member of the bumpers. At low speeds, the flexible bumpers are deformed but then return to their original shape. At higher speeds, easily replaceable deformation elements called “crash boxes” (incorporated into the frame on the front and rear cross members) absorb sufficient energy in a minor impact to ensure that the side members behind them are not deformed. In special repair crash tests, it has been demonstrated that because the front-end structure becomes progressively stiffer toward the rear, damage to the vehicle body at an impact speed of up to about nine mph remains confined to the immediate points of impact.

ABS Anti-Lock Brakes
Another Mercedes-Benz safety first, ABS prevents dangerous wheel lockup during heavy braking and works on wet or icy surfaces as well as on dry ones. When the driver hits the brake pedal in an emergency situation, ABS uses wheel-speed sensors to sense impending lockup, then automatically releases the brakes in split-second pulses so that the vehicle can retain its directional stability and can still be steered.

Brake Assist
Pioneered by Mercedes-Benz, Brake Assist can potentially shorten stopping distances during emergency braking. Brake Assist features a sensor on the brake pedal linkage which allows the computer to recognize unusually fast pedal application speed that identifies an emergency braking situation. The system then applies full braking force by actuating a special valve on the brake booster unit. While Brake Assist operates independently of the ABS anti-lock brakes, it does rely on ABS to prevent wheel lockup during full brake force application.

ASR Traction Control
ASR is an abbreviation that originally stood for a German term meaning “anti-slip regulation.” ASR traction control uses the wheel speed sensors, which are as good at identifying wheel slippage as they are at recognizing wheel lockup. Processing this valuable information in a split-second, traction control can apply the brakes to any slipping drive wheel, improving traction as a result.

Adaptive Braking
The new GLK incorporates an adaptive braking system that includes a brake proportioning feature with sensors to measure deceleration and cornering forces as well as rear suspension movement. Based on this data, the system can modulate the amount of brake force on each wheel to maximize its contribution to the overall braking effort.

This system includes brake-drying and hill-start assist features. Whenever the wipers are turned on, the brake pads will automatically (and imperceptibly) touch the brake discs occasionally to clear them of water, which helps ensure consistent braking in wet weather. Hill-start prevents the car from rolling backwards when stopped on a steep hill by briefly keeping brake pressure applied until the driver touches the gas pedal.

ESP – Electronic Stability Control
The first-ever passenger vehicle with a stability control system was the 1996 Mercedes-Benz S600 coupe, and like all current Mercedes models, the new GLK features Electronic Stability Program (ESP) as standard equipment. Even the “ESP” abbreviation helps explain the system’s benefit – in essence, ESP works invisibly, seemingly intuitively, to help keep the car going exactly where the driver points it, under driving circumstances that might otherwise lead to loss of control and a possible accident without the system.

Using electronic sensors and computer logic, the system measures if the car is going in the direction it is being steered. If there’s a difference between what the driver is asking (primarily through the steering wheel) and what the vehicle is doing, the system corrects with split-second speed by applying one of the left or right-side brakes, even before the driver may sense any changes.

ESP uses the angle of the steering wheel and the speed of the four wheels to calculate the path being steered, and it gets electronic signals about lateral acceleration and vehicle yaw rate to measure what the car is actually doing. Yaw rate describes the speed at which a vehicle rotates around its vertical center axis, and it can be demonstrated by rotating a small model car on a toothpick stuck down through its roof.

ESP measures any tendency toward understeer (when a car is slow to respond to steering changes, causing it to “plow”) or oversteer (when the rear wheels try to swing around, causing the car to “fishtail”). Whenever it senses understeer in a turn, ESP increases brake pressure to the inside rear wheel. With an oversteer tendency, it increases brake pressure to the outside front wheel.

ESP is effective during acceleration, braking and coasting. The system enhances driver control and helps maintain directional stability in turns as well as when driving straight-ahead, including on uneven surfaces and over patchy snow, ice or gravel.

Tire Pressure Monitoring
All tires slowly lose some air through the rubber, and as a result, maintaining correct tire pressure is easy to overlook. At the least, low tire pressure degrades handling and causes more rapid tire wear, but it can also lead to a tire blowout that can trigger a collision or rollover.

On the new GLK, sensors mounted on the inner wheel inside each tire transmit radio signals about tire pressure, temperature, direction of rotation and an ID number (to identify each wheel) to a control unit in the trunk. If there’s significant pressure loss, a “Check Tires” warning message appears in the central display, and if there’s a rapid pressure loss, a “Caution Tire Failure” warning appears. The warning disappears automatically when correct tire pressure is restored.


Conclusion

It’s clear that the new GLK will bring new energy and relevance to the Mercedes-Benz sport utility family. With its focus on good fuel efficiency and renewed emphasis on agility, safety and comfort, the GLK should prove very popular.

As social and economic change is transforming the auto industry, consumers are looking for more socially responsible alternatives for their personal transportation. For many, a GLK is the new right-sized SUV, and it supports the nation’s latest environmental initiative.

The Mercedes-Benz sport utility family began in 1997 with the birth of the highly successful M-Class, which rocked the auto industry with its innovative technology and car-like performance and safety. The Mercedes-Benz SUV lineup now spans a full range of practical, luxurious models – from the premium GL-Class to the new mid-size GLK.

As Mercedes-Benz USA sets all-time sales records each year, the challenge becomes greater, and the proverbial bar is raised for others to follow. Already with the broadest product line in the automotive luxury market, Mercedes-Benz is well positioned for the future with the new GLK.













































































































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