Test Drive: 2010 Mercedes-Benz S400 Hybrid

The S400 Hybrid sets standards for Eco-Chic

?Many people perceive the S-Class sedan from Mercedes-Benz to be one of the top luxury vehicles in the world, and now, an S400 Hybrid model has been added to the restyled S-Class lineup. The innovative 2010 S400 Hybrid delivers V8-like power, but with the fuel economy normally only provided by a four-cylinder engine. The S400 features the world?s first lightweight, high- capacity lithium-ion battery designed specifically for automotive use.? The battery works with a 20-horsepower electric motor and a 275-hp V6 gasoline engine providing hybrid power with fuel economy estimated at 30 miles per gallon on the highway ? a 30 percent improvement in fuel economy.

All S-Class models benefit from enhanced and freshened styling which includes: a more streamlined front grille, larger outside mirrors and a new front bumper with a chrome strip below the air intakes. New active bi-xenon headlights include LED turn signals along the lower edge, and all S-Class models except the S400 HYBRID now come with LED daytime running lights on each side of the bumper.? Other exterior changes include LED taillights and exhaust outlets integrated within a recontoured rear bumper fascia.

For 2010, the S-Class comes with an upgraded wood / premium-leather steering wheel, and standard ambient lighting may be chosen from three hues ? polar (ice-blue), neutral (white) and solar (amber).? A rear-seat entertainment system is now also available.

Not only does the electric motor generate 20 horsepower on its own, it also produces an impressive starting torque of 118 pound feet. The 275 horsepower, Atkinson-Cycle V6 delivers 258 pound feet of torque. A powerful onboard computer controls the hybrid system, recalculating the best operating mode 160 times per second. The system is capable of up to 50 million calculations per second and works to maintain an ideal balance between fuel economy and performance.

The 120-volt lithium-ion battery weighs less than most other batteries and takes up less space, but provides a high energy density for its size, enabling it to be installed in the engine compartment, leaving the car?s ample trunk capacity and spacious interior unaffected.? The lithium-ion battery features a high-strength?steel housing, a separate cooling circuit, and cells that sit in a special gel that dampens any jolts and vibration. ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ??

The S400 is categorized as a ?mild hybrid?, with its gasoline engine and electric motor working together for responsive performance, and its driveline includes a specially configured seven-speed automatic transmission, a transformer to power the 12-volt vehicle system and intelligent operating electronics. The electric motor is disc-shaped, and is mounted in the torque converter housing, between the engine and transmission.

The hybrid system includes a convenient start-stop function that turns off the gasoline engine below nine mph when braking to a stop.? When the S400 HYBRID is at a traffic light, for example, the gasoline engine is off, but the AC compressor and steering pump are operated electrically, so the air conditioning and power steering continue to function fully.? When the brakes are released, the gasoline engine starts automatically, and works with the electric motor producing a seamless performance.?

During braking, the electric motor acts as a generator, recovering kinetic energy and storing it in the lithium-ion battery.? Under heavy braking, the vehicle?s conventional brakes also come into play.? Recovered energy is stored in the battery and re-used whenever the electric motor is running.

The Mercedes-Benz S400 Hybrid provides the same interior spaciousness, luxury and convenience features offered in all other S-Class models. It is differentiated by unique seven-twin-spoke 18-inch wheels (19-inch five-spoke AMG-style wheels are available as an option with the Sport Package) and HYBRID logos on the trunk lid and dash as well as BlueEfficency badging on the front fenders.? A special hybrid pictogram within the speedometer shows the energy flow, energy recovery and battery charge.

Safety and Security issues are covered by stat-of-the-art technologies such as:? Adaptive, dual stage front airbags; 3-point seatbelts with pre-tensioners and Force Limiters; ISOFIX anchor and tether system; Side airbags front and rear; full-length head protection curtain; NECK-PRO active head restraints; 4-wheel disc brakes with ABS, BAS, ESC; PRE_SAFE Predictive Protection System and Tire Pressure monitoring system. There are more features, including the industry?s first Adaptive Brake Lights, but space here is limited.

My test Mercedes-Benz S400 Hybrid sported a Diamond White metallic exterior finish, while the interior was executed in Cashmere toned Savanna leather and polished wood and chrome trim accents. The base price was set at $87,950 while optional fare elevated the final sticker price to $111,030. Extra charges were incurred for: the metallic paint; woo& leather premium steering wheel; Night View Assist PLUS with pedestrian detection; the Premium Package; Driver Assistance Package; Sport Package; Rear Seat Package; Rear Seat Entertainment Package; and Destination and Delivery Package.

SUMMARY:? The Mercedes-Benz S400 Hybrid is every bit an S-Class vehicle, but one with a conscience and a nod toward ecological betterment. It may be properly referred to as Eco-Chic. While there are V8 and V12 versions of the S-Class, the S400 with its V6 power cranks out the performance of many V8s, but literally delivering the same fuel economy as many four-cylinder engines.

It is entirely possible to drive the S400 without realizing that one is indeed piloting a V6-powered vehicle, and, a ?mild-hybrid? vehicle at that. The S400?s performance comes across as totally normal except for the gasoline engine shutting down when stopped, and starting up again automatically when the brake is released.

The S400 is every bit as plush as all other S-Class models, without sacrificing any of the amenities or available features. Plenty of acceleration is instantly on tap and the handling is quite nimble for a vehicle that weighs in at nearly two and a half tons. There is a certain sense of its overall mass, but it is certainly a far cry above and beyond so called ?land yachts? of yesteryear, maintaining a civilized stability and comfortable ride compliance.

In the final analysis, the S400 allows the discerning consumer to enjoy the benefits of one of the finest 4-door luxury sedans globally available while leaving a smaller footprint on the environment. It may not be the ultimate solution to ecological issues, but it is certainly a positive step forward.

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