In January 2005, the new M-Class in model series W 164 celebrated its world première at the North American International Auto Show (NAIAS) in Detroit. The completely newly developed vehicles were again built at the US plant in Tuscaloosa, Alabama, where they replaced the predecessor model series W 163, which was also produced there. With a total of almost 648,000 units produced since 1997, it had proved to be a best-seller and at the same time a trendsetter for the new sport utility vehicle (SUV) market segment.
Mercedes-Benz wanted to further expand this market position with model series W 164. To this end, the engineers further advanced the capabilities of the multifunctional vehicle for both on-road and off-road use. The key element here was the introduction of a unibody construction instead of the ladder-type frame used in the previous generation. Thanks in part to newly designed points of load application between the chassis and body, torsional stiffness was significantly higher than previously. In addition to smooth-running six- and eight-cylinder engines, newly developed axles and the optional AIRMATIC air suspension, combined with the Adaptive Damping System (ADS) to control damping in line with the current situation, contributed to even better long-distance driving comfort.
At the market launch, the M-Class was available with four different engines, three of which were new developments. In the ML 280 CDI and ML 320 CDI models, the new V6 diesel engine of the OM 642 series was used in two output levels, with 140 kW/190 hp in the entry-level model and 165 kW/224 hp in the ML 320 CDI. The peak torque values were 440 Nm at 1400 rpm and 510 Nm available from 1600 rpm. Thanks to third-generation common-rail direct injection and state-of-the-art piezo injectors, the average standard fuel consumption of the diesel models was 9.4 to 9.6 litres per 100 kilometres, making these models some the most economical in their segment. Also new was the V6 petrol engine of the ML 350 with an output of 200 kW/272 hp and a maximum torque of 350 Nm. At the top of the engine range was the ML 500's eight-cylinder engine, already familiar from the previous model, which now produced 225 kW/306 hp. In terms of power and torque, the new and revised drive units outperformed their predecessors by up to 38%, while at the same time fuel consumption was reduced by up to 10% thanks to optimised aerodynamics.
The power transmission was now handled as standard by the world's first 7-speed automatic transmission 7G-TRONIC, which was introduced in autumn 2003 and operated in the M-Class via the new DIRECT SELECT technology with the aid of a selector lever mounted close to the steering wheel. Additional steering wheel gearshift buttons made it possible to quickly change the seven gears manually.
The SUV set standards in the area of safety: Occupant protection was based on the unibody construction's large deformation zones and the standard use of cutting-edge technology from the luxury class. These included adaptive, two-stage airbags for the driver and front passenger, side airbags at the front, window airbags as well as belt tensioners and belt force limiters on all seats. In the event of a rear-end collision, the newly developed NECK-PRO crash-responsive head restraints, which are available as an option, offered additional protection for the driver and front passenger. The PRE-SAFE® preventive occupant protection system was also available as an option. The multi-award-winning technology was activated in critical, hazardous driving situations to prepare the occupants and the car for an imminent collision. As a precaution, PRE-SAFE® tightened the seat belts for the driver and front passenger, optimised the individual adjustment of the optionally available fully electrically adjustable front passenger seat and closed the potentially installed sunroof in the event of an impending rollover. The PRE-SAFE® system used electronic networking with the ABS anti-lock braking system, with BAS Brake Assist and with the ESP® Electronic Stability Program, whose sensors detected critical driving conditions.
Mercedes-Benz enhanced the M-Class' off-road performance, which was provided by the 4MATIC permanent all-wheel-drive system, with the further developed 4ETS traction system, which now had additional functions such as off-road ABS, Start-off Assist and Downhill Speed Regulation as standard. In terms of all-wheel-drive technology, there was a choice of two equipment variants for the M-Class models, which met different requirements: Firstly, the basic version and secondly, the optional new Offroad Pro Engineering Package. It was designed to cope with the most difficult off-road passages and included a two-stage transfer case with low-range reduction, manually or automatically engageable 100 per cent differential locks between the front and rear axles as well as on the rear axle, and AIRMATIC air suspension tuned for demanding off-road use. The latter made it possible to increase the ground clearance by 110 mm to up to 291 mm and the fording depth to up to 600 mm (standard: 500 mm).
The engineers had developed new front and rear axles for the M-Class, which now featured a unibody construction: A double wishbone axle at the front ensured low road roar and tyre vibration with impressive driving dynamics, while a four-link design was used at the rear. Standard light-alloy wheels with wide-base tyres of sizes 235/65 R 17 (V6 models) and 255/55 R 18 (V8 model) not only offered a high level of traction, but also accentuated the sporty appearance of the M-Class.
The body design was characterised by an interplay of strongly contoured surfaces and taut lines. With the flat windscreen, the striking wings and the shoulder line rising towards the rear, the design idiom set unmistakably sporty accents, which were further emphasised by slightly altered proportions due to a wheelbase that was extended by 95 mm to 2915 mm compared to the previous generation.
This also benefited the interior, which not only featured particularly high-quality materials and a more pleasant surface touch and feel, but also significantly more space on all seats. The distance between the front and rear seats increased to 880 mm compared to the previous model, putting it on a par with a luxury-class saloon. In addition, knee room and elbow room for rear passengers were improved by 35 mm and 32 mm, respectively.
Customers were able to select the seats of the new M-Class according to their individual comfort requirements: In addition to front seats with electric height, tilt and backrest adjustment as standard, sports seats with special backrest contours were also optionally available. The rear seats were split 60:40 and could be folded down. If desired, both seat cushions could be removed to create a flat loading area more than 2.10 metres long. In addition, the maximum load volume of 2050 litres (according to the VDA measurement method) significantly exceeded that of comparable competitors. The EASY-PACK system, which could be optionally specified, made it easier to utilise the load compartment with, among other things, an electrically operated tailgate and a set for securely tying down loads.
State-of-the-art assistance systems from the Mercedes-Benz luxury class enhanced both comfort and safety in the new multifunctional vehicle. The new generation of M-Class models was optionally available with the advanced Multi-Zone THERMOTRONIC automatic climate control system, the PARKTRONIC parking aid, the COMAND APS control and display system with Europe-wide DVD navigation and bi-xenon headlamps including active light function and cornering light.
As the suspension, brake system and steering of the W 164 model series had already been adapted to the stresses of towing a trailer during the design phase, the M-Class models were particularly suitable as towing vehicles. If a trailer coupling was ordered ex-factory, customers also benefited from the new ESP® trailer stabilisation system. The system recognised any potentially developing trailer sway and effectively reduced it with the help of the ESP® sensors by means of wheel-selective, alternating braking interventions.
The dynamic AMG outfit was also available for the M-Class vehicles in time for the market launch. The AMG Styling Package was available for all engine variants and consisted of front and rear aprons painted in vehicle colour, with vertical brushed stainless-steel inserts at the front. Large, round fog lamps with chrome rings and optional cornering light were also added. Four air intakes with the black expanded metal grid familiar from racing cars and the strikingly designed front underride guard emphasised the sporty character of this version. On the rear apron, bulges for the tailpipes of the two-pipe exhaust system set special visual accents. The AMG outfit was rounded off by AMG light-alloy wheels of size 8.5 x 19 painted sterling silver.
The market launch of the W 164 started in the USA in April 2005, with vehicles rolling into showrooms in Europe in the summer. In July, shortly after the market launch, around 26,500 orders had already been placed. The new models had previously been launched with great success in the United States, which was regarded as the premium SUV's main sales market, and had made a significant contribution to the sales success of Mercedes-Benz in the USA.
At the beginning, the gross list prices in Germany ranged from 46,342.00 euros for an ML 280 CDI 4MATIC to 63,220.00 euros for an ML 500 4MATIC.
A few weeks later, at the International Motor Show (IAA) in Frankfurt/Main in September 2005, Mercedes-Benz presented the ML 63 AMG as the new flagship model in model series W 164. The performance model was powered by a 6.3-litre V8 engine producing 375 kW/510 hp and a maximum torque of 630 Nm at 5200 rpm, making the AMG engine the most powerful naturally aspirated eight-cylinder production engine in the world at the time. The unique combination of high-rev concept and large displacement resulted in an unusual mix of the engine's propensity for high rpm and strong pulling power at low revs.
The AMG version accelerated from a standstill to 100 km/h in just 5.0 seconds and had an electronically limited maximum speed of 250 km/h. Compared to the previous ML 55 AMG model in model series W 163, the ML 63 AMG delivered a 46% increase in power and 23% more torque. The power transmission was handled by an AMG SPEEDSHIFT 7G-TRONIC automatic transmission. Three shift programs specially tailored to the sporty power delivery of the engine allowed the performance potential to be exploited with ease. The shift programs "S" (Sport), "C" (Comfort) and "M" (Manual) could be selected via a switch in the centre console and differed in their shift characteristics and speed.
The AMG sports suspension based on the AIRMATIC air suspension specified in the top-of-the-range model allowed high cornering speeds and also impressed with its precise steering behaviour and low body roll while offering long-distance comfort. The air suspension had AMG-specific spring struts and the specially tuned ADS Adaptive Damping System. A level control system automatically lowered the body at higher speeds. In conjunction with the permanent AMG all-wheel drive, which was characterised by an individual torque distribution of 40% front to 60% rear, this configuration resulted in driving dynamics that were unique in this vehicle category. Contact with the road was established by 19-inch AMG light-alloy wheels in a 5-spoke design with high-sheen finish. As an option, 20-inch AMG 5-spoke light-alloy wheels with 295/40 R 20 tyres were available. The ML 63 AMG was decelerated by a high-performance brake system with large ventilated and additionally perforated brake discs all round.
The design of the ML 63 AMG emphasised its exceptional position in the M-Class model range. The typical AMG styling of the front and rear aprons as well as the specific radiator grille and the wing extensions were characteristic. Stainless-steel side running boards, darkened tail lamps and the AMG sports exhaust system with two chrome-plated twin tailpipes were further visual features of the performance version. Sportiness also dominated the interior: Highlights included the AMG sports seats upholstered in nappa leather with Alcantara inserts in the shoulder area, multicontour function and seat heating, the AMG ergonomic leather sports steering wheel with gearshift buttons, AMG door sill panels, the stainless steel sports pedals with rubber studs and the AMG instrument cluster with its own lettering, red hands and 320-km/h speedometer scale.
The market launch of the ML 63 AMG started in the second quarter of 2006 with gross list prices starting at 96,164.00 euros.
Right from the start, the overall design of the new M-Class, which was geared not least towards the best possible passive safety, earned the highest praise from independent test institutes. In 2005, the US National Highway Traffic Safety Administration awarded the 5-star rating for crash test performance in accordance with the US NCAP procedure. The M-Class was one of the first SUVs ever to be awarded this top rating in both frontal and side impacts.
In summer 2006, Mercedes-Benz expanded its range of diesel-powered models with the new top-of-the-range ML 420 CDI 4MATIC. In order to standardise the designation of the vehicle types across all model series, the suffix 4MATIC had already been added to all M-Class model designations from the spring – despite the fact that all-wheel drive was fitted as standard. The 4.0-litre diesel V8 in the ML 420 CDI 4MATIC featured four-valve technology, biturbo charging and variable turbine geometry. The torque of the 225 kW/306 hp compression-ignition engine was 700 Nm over a rev range from 2000 rpm to 2600 rpm. The increase in performance of the revised diesel V8 compared to the version used in the ML 400 CDI of the previous model series was primarily due to the third-generation common-rail, high-pressure injection system with a maximum injection pressure of 1600 bar.
The ML 420 CDI 4MATIC accelerated from a standstill to 100 km/h in 6.8 seconds and reached a maximum speed of 235 km/h. The new top-of-the-range diesel model took just 6.0 seconds to sprint from 60 km/h to 120 km/h in third gear. In conjunction with the 7G-TRONIC automatic transmission, the high power reserves ensured relaxed driving at low engine speeds and thus favourable fuel consumption values in relation to the performance potential. With a particularly economical driving style, the diesel engine consumed just 9.1 litres of fuel per 100 kilometres, while the average standard consumption was a moderate 11.1 to 11.3 litres. Like all other diesel engines used in the M-Class, the unit used in the ML 420 CDI 4MATIC was equipped with a maintenance-free diesel particulate filter, which reduced untreated emissions by 99%. The Mercedes-Benz premium SUV thus clearly undercut the limits of the Euro 4 emissions standard.
The gross list price for the muscular diesel model at market launch was 65,540.00 euros.
In summer 2007, Mercedes-Benz introduced a new V8 petrol engine for the ML 500 4MATIC. A unit of the M 273 engine family was now installed. With a displacement of 5461 cc, the engine, which had two overhead camshafts per cylinder bank and four-valve technology, provided an output of 285 kW/388 hp and a peak torque of 530 Nm – 60 kW/82 hp or 70 Nm more than the previous engine. This considerable increase in power resulted in significantly improved acceleration performance: The ML 500 4MATIC now completed the sprint to 100 km/h in 5.8 seconds, more than 1 second faster than its predecessor. However, the increased engine power was not associated with increased fuel consumption; in fact, the average standard fuel consumption of 12.8 to 13.1 litres of premium petrol per 100 kilometres was even slightly lower than before.
To mark the tenth year of M-Class production, Mercedes-Benz presented the "Edition 10" special model in July 2007. Some 600,000 vehicles of the first generation had been sold worldwide by the time they were replaced by the completely newly developed models of model series W 164, and with around 250,000 deliveries by the summer of 2007, the current models had seamlessly built on this success. The equipment package for the "Edition 10" variant included 20-inch light-alloy wheels, bi-xenon headlamps, dark tail lamps, special body colour accents in a titanium look, and Edition logos on the wings. The sporty and luxurious interior featured a two-tone all-leather interior, sports instruments and stainless steel sports pedals. The Edition equipment was available for all M-Class models with the exception of the ML 63 AMG 4MATIC. Vehicles specified accordingly could be ordered from autumn 2007 at gross list prices of between 49,920.50 euros for an ML 280 CDI 4MATIC and 69,555.50 euros for an ML 500 4MATIC.
In the production cycle prior to the first facelift of model series 164 scheduled for spring 2008, the mid-range engine versions of the M-Class proved to be by far the most popular for both petrol and diesel models. The petrol-powered ML 350 4MATIC took the leading position with just under 126,000 units, followed by the diesel-powered ML 320 CDI 4MATIC with around 116,500 vehicles. The ML 280 CDI 4MATIC entry-level model took third place in the production statistics with around 35,000 units. The particularly powerful M-Class versions clearly took a back seat in the popularity stakes. The ML 500 4MATIC performed best here, accounting for just under 8,500 vehicles, while slightly more than 7,000 units of the ML 63 AMG 4MATIC and slightly fewer than 7,000 units of the ML 420 CDI 4MATIC were produced.
