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2014 Sprinter van for US standard with new 2.1L diesel; new driver assistance features

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2014 Sprinter. Click to enlarge.

The new MY2014 Mercedes-Benz Sprinter van for the US now features a 2.1L, 4-cylinder diesel with a t-speed automatic transmission as standard. The familiar V6 diesel is available as an option.

Since 2010, all Sprinters in the US have been powered by BlueTEC diesel engines, marking the first use of BlueTEC technology, with its selective catalytic reduction (SCR) exhaust aftertreatment system, in the commercial van market here. The 2.1-liter four-cylinder diesel engine produces 161 hp (120 kW) and 265 lb-ft (359 N·m) of torque at 1,400-2,400 rpm.

With an 83 mm bore and a 99 mm stroke, the engine features an undersquare configuration in the interests of high tractive power. The two overhead camshafts actuate 16 intake and exhaust valves. The camshafts are driven by a combination of gearwheels and a short chain. The common rail injection system operates at a maximum injection pressure of 26,000 psi. The fuel is injected by means of magnetic injectors and seven-hole injection nozzles. Charging takes place at all times via a two-stage exhaust-gas turbocharger system.

Maximum torque is available right from low engine speeds and over a broad engine speed range. The engines attain both a high specific power output and high torque. This downsizing enables lower fuel consumption, accompanied by low emissions and optimum weight.

A Lanchester balancer with two counter-rotating shafts, the camshaft drive positioned further to the rear and a two-mass flywheel all contribute to the engine’s extremely smooth running characteristics. A combination of exhaust gas recirculation with two-stage cooling and the SCR technology with AdBlue injection for the BlueTEC engines and a particulate filter delivers clean exhaust emissions.

The 4-cylinder Sprinter features a 7-speed automatic transmission with torque converter—the only 7-speed automatic transmission to feature in a van—is refined for maximum fuel economy. The improved damping technology results in a lower tendency to generate noise and hum. The reduced slip on the lockup clutch gives a more direct connection to the accelerator pedal and therefore provides greater agility, the company says.

The development engineers have additionally adapted the automatic transmission’s shift points precisely to the engine characteristics, also optimizing the oil’s heat-up behavior in the cold running phase in this respect, along with the torque converter’s hydraulic circuit. This results in faster heating-up of the oil, therefore minimizing frictional losses after cold starting.

In the interests of low-friction and economical running, modifications have been undertaken here down to the microgeometry of the differential’s tooth flanks, the precision of installation has been further improved, and the oil flow has been optimized to reduce churning loss while the axle is running. These measures have been applied to all axle variants.

The optional 3.0L V6 diesel motor (188 hp, 325 lb-ft) is an undersquare engine (bore x stroke: 83 x 92 mm) based on an aluminum crankcase with a V angle of 72 degrees. Offset rod journals and a balancer shaft result in an extremely smooth-running engine. Its technical refinements include a total of four duplex chain-driven overhead camshafts and common rail injection with piezo injectors and eight spray holes per nozzle.

Accessory equipment. The engineers at Mercedes-Benz have also fine-tuned the Sprinter’s accessory equipment for maximum economy.

The generator management system has been optimized for even greater efficiency. Intelligent generator management has the alternator giving priority to charging the battery during braking and coasting. During acceleration and cruising, the full engine output is available to the drive system. The electric fuel pump controls the fuel supply for the Sprinter according to requirements—i.e. with a variable delivery rate. The compressor of the optional air conditioning system incorporates a freewheel, so that it is only active when the air conditioning is on.

Four new assistance systems for safety. A key focus in developing the new Sprinter was on a whole range of new assistance systems—including world premieres in the van segment. New available features to be premiered with the new Sprinter are Collision Prevention Assist; Blind Spot Assist; Highbeam Assist; and Lane Keeping Assist.

Collision Prevention Assist is designed to help prevent serious rear-end collisions and includes a proximity warning function and adaptive Brake Assist. It warns the driver when the distance from the vehicle ahead is too small and, at a further escalation level, when there is an acute danger of collision.

The radar-based proximity warning assistant helps the driver to maintain an appropriate safe distance from the vehicle in front. A radar sensor in the front bumper continuously measures the distance from the vehicle ahead in the same lane and the relative speeds of the two vehicles. The proximity warning assistant calculates the necessary safe distance on the basis of this information. Collision Prevention Assist is operational from a speed of approximately 12 mph (19 km/h).

A visual warning (warning lamp in the instrument cluster) is triggered as soon as a vehicle ahead is detected and the distance to the vehicle ahead drops below a specific limit, indicating that the distance is not safe.

The dynamic proximity warning function is triggered as soon as the driver’s vehicle approaches the detected vehicle ahead with a high difference in speed. In this case, both a visual and an acoustic warning is given. Both warnings allow the driver to carry out emergency braking or evasive maneuvers. The driver can switch off this assistance function as necessary.

Similar to ESP, the Brake Assist pro function cannot be switched off by the driver. It is continuously active in the background, monitoring the current operating conditions and the current driving situation. Support from Adaptive Brake Assist is triggered after the dynamic proximity warning when the distance between the Sprinter and the vehicle ahead closes too rapidly and driver initiates panic braking.

Adaptive Brake Assist is able to support emergency braking according to the relative speed/relative acceleration and the distance from the identified object. When the driver fails to apply sufficient brake power, Adaptive Brake Assist provides additional boost to generate just enough additional deceleration to help avoid an accident. This also gives the traffic behind the longest possible response time to avoid a rear-end collision.

The driver can override the intervention by adaptive Brake Assist at any time, i.e. if the driver initiates harder braking than the system identifies as necessary, the driver’s action will take priority. Conversely, intervention will be stopped if the driver carries out an evasive maneuver, takes his or her foot off the brake pedal or presses the accelerator pedal.

The optional new feature Blind Spot Assist—another first for the van segment—additionally helps the driver by warning them of other vehicles in the blind spot during lane changing.

The new Blind Spot Assist function is operational from a speed of approx. 20 mph (32 km/h) . It is based on a total of four close-range radar sensors. These are installed on the right and left behind the side rub strips in the area of the B-pillar and the rear corner pillar and cover the area of the neighboring lanes. When the sensors identify a car or motorcycle in the blind spot while the vehicle is on the move, a red warning signal appears in the exterior mirror on the respective side.

When the assistance system detects that the driver has activated the indicator and thus intends to change lane despite the warning, he or she receives an additional warning in the form of an acoustic signal and the red warning symbol begins to flash. This assistance function can be deactivated by the driver.

In Lane Keeping Assist, a camera behind the windshield films the road ahead. An integrated electronic control unit measures the recorded data continuously, identifying the road surface and markings by reference to differences in contrast. If the van threatens to cross the side marking without the indicator having been activated or without parallel changes to the accelerator or brake pedal position, the control unit will conclude that the vehicle is leaving its lane unintentionally and will warn the driver with an acoustic signal.

Lane Keeping Assist is active from a speed of approximately 40 mph (64 km/h) and responds not only to white lines on the road but also to yellow markings at construction sites. The driver can switch this assist system off as necessary—when driving along narrow and winding country roads, for example. Conversely, Lane Keeping Assist helps the driver to stay on course when there is little room for maneuvering—at highway construction sites, for example.

The new Highbeam Assist feature is a first in the Sprinter’s class. It guarantees optimum illumination of the road by switching high beam on or off according to the given situation. The path of the road, pedestrians or dangerous spots are now recognizable even earlier and more reliably. At the same time, Highbeam Assist also reduces the possibility of oncoming traffic or vehicles ahead being blinded.

The system is based on a camera on the inside of the front windscreen which observes the traffic situation in front of the vehicle. When the camera detects vehicles or motorcycles travelling towards or ahead of the Sprinter, the high beam is automatically dipped to low beam. Highbeam Assist is able to distinguish between moving and stationary objects. When the road is clear once again, the assistance system switches back to high beam. The camera system also responds to road lighting by deactivating high beam automatically— when passing through built-up areas, for example. Highbeam Assist operates at vehicle speeds above 22 mph (35 km/h), and is available for both halogen and bi-xenon headlamps.

European powertrains. In addition to 4- and 6-cylinder diesel units with outputs ranging from 70 kW (95 hp) to 140 kW (190 hp), the 2014 Sprinter in Europe is also available with a Euro VI compliant supercharged four-cylinder gasoline engine featuring direct injection. The engine generates 115 kW (156 hp) from a total displacement of 1.8 liters. The engine is also available in a natural gas variant with the same performance.

Power is transmitted either by the ECO-Gear six-speed manual transmission or the 7G-TRONIC PLUS seven-speed automatic transmission with lock-up clutch, which is the only system of its kind to be found in a van.

The new Sprinter meets the future Euro VI emissions standard in all of its engine variants.

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