2011 Mercedes-Benz S400 Hybrid Road Test and Review

The 2011 Mercedes-Benz S-Class is available in five different designations - S400 Hybrid, S550, S600, S63 AMG and S65 AMG – with the S400 Hybrid continuing to be the “base” model. Now in its second year, the S400 Hybrid received a significant price increase to its 2011 starting MSRP of $91,000. Even with such a high starting price, sales of the 2011 S-Class were up almost 18 percent in August (compared to last August). Adding in a handful of comfort, styling and technology options, the S400 Hybrid used for this review had an as-tested price of $102,115 including the destination charge. Despite its price increase of just over $3,000 for 2011, the S400 Hybrid is still the least expensive hybrid sedan in its class.

The Toyota Prius is easily the poster child for hybrid-electric vehicles, but those desiring a hybrid with more luxury and technology than a compact hatchback can provide will find that the 2011 Mercedes-Benz S400 Hybrid is more than capable of filling this role. Despite being in a relatively niche market as a full-size, hybrid luxury sedan, the S400 still has quite a bit of competition including the Lexus LS 600h, BMW ActiveHybrid 750i, Porsche Panamera S Hybrid and Audi A8 Hybrid. The Lexus, of course, is the originator of this segment, but considering the fact the S400 Hybrid is a mild hybrid, it allows the Mercedes to start almost $20,000 less than the Lexus while at the same time getting better fuel economy on the highway. It isn’t likely that the Mercedes-Benz S400 will challenge the BMW ActiveHybrid 7 Series’ title of “world’s fastest street-legal hybrid” anytime soon, but this hybrid S-Class will always hold the distinction of being the first mass-produced car to use a lithium-ion battery.

Aside from the model designation and the “hybrid” badges on the decklid, it is hard to distinguish the 2011 Mercedes-Benz S400 Hybrid from some of the other S-Class models. After only a year since a substantial exterior styling update for 2010, the 2011 S-Class carries over untouched. The biggest changes made to the eighth-generation were to the front and the rear of the car. Up front, redesigned Bi-Xenon headlights now utilize LED parking lights and turn signals and thin strips of LEDs are also found in the front fascia for the daytime running lights; new LED taillights replaced the Maybach-like body color accents. The updated S-Class still features the bulging wheel arches and the surprisingly sleek roofline, and this test vehicle adds an even sportier look thanks to the $5,900 Sport Package which includes AMG-branded, five-spoke 19-inch wheels and a more aggressive body kit including fascias and side skirts. Our 2011 S400 Hybrid tester was finished off in a dark – almost black – shade of blue called Capri Blue.

On top of everything else, the 2011 Mercedes-Benz S400 Hybridbrings eight generations of luxury to the hybrid segment with an interior that delivers class-leading comfort, convenience and technology. As expected from a $100,000 sedan, there is plenty of wood and leather trim throughout the cabin with a rich Eucalyptus wood used on the steering wheel, instrument panel, door panels and center console to accent the two shades of leather. For the driver, the instrument gauge cluster features a large LCD screen that shows the speedometer as well as other information including the status of the car’s hybrid system and battery state of charge.

Unlike most other hybrids, the S400’s lithium-ion hybrid battery is mounted under the hood (it is about the same size as a conventional lead battery), so it does not lose any trunk or, most importantly, rear-seat volume. Even without options like rear-seat air conditioning, heated and ventilated rear seats or power-adjustable rear seats (which are all available on other S-Class models), the back-seat accommodations are still very luxurious and spacious. With all of the high-tech and high-end features found inside the S400 Hybrid, Mercedes even managed to add some low-tech convenience like the dual-hinged front center console lid which gives the driver and front passenger equal access to the center console without impeding any of the rear-seat space.

On this test vehicle, the front passengers get the added comfort of the “Active multicontour” front seats which provide active adjustments to the side bolsters while the car is turning while also providing a four-stage massage function. The navigation and audio systems (as well as other vehicle functions) can be adjusted using the COMAND controller found on the center console (under the leather-covered number pad) with all of the information displayed on the display above the center stack. Showing its chauffeur roots, the driver can also easily control the position of the front passenger seat to increase the legroom for rear occupants.

With a starting price of $91,000, the 2011 Mercedes-Benz S400 Hybrid comes with plenty of standard features, but it is also available with plenty of optional goodies as evident by out test vehicle. In addition to the $5,900 Sport Package, this S400 was also equipped with the Premium Package which added an extra $3,630 to the bottom line. The Premium Package adds the aforementioned Active Multicontour front seats as well as keyless start, Parktronic parking guidance and a rearview camera. Finally, our S400 test vehicle came with Mercedes’ innovative SplitView which added only $710 to the car’s price, but it is more than worth the cost as it allows the front passenger to watch movies on the center display screen while the driver continues to see the regular, non-distracting information such as audio, navigation, etc.

Introduced for the 2010 model year, the Mercedes-Benz S400 Hybrid is powered by a 3.5-liter V-6 that produces 275 horsepower and 258 lb-ft of torque, and Mercedes-Benz pairs this engine with a mild hybrid system that consists of a 120-volt lithium-ion battery and a 20-horsepower drive unit. The electric components of the hybrid system give the car a combined out of 295 hp and 284 lb-ft of torque with a flat torque curve that kicks in at 2,400 rpm up through 5,000 rpm. Yes, this is the same engine bay that also accommodates the 621-horse-power, 6.0-liter twin-turbocharged V-12 in the S65 AMG, but while the AMG is built for speed, the S400 Hybrid is made for optimizing fuel economy.

Since it uses a mild hybrid system, the S400 is not able to operate under all-electric power, but the system does help to conserve gasoline primarily by shutting off the engine at stops and using regenerative braking. As is the case with most hybrid systems, the S400’s biggest fuel economy gains are in the city with EPA estimates of 19 miles per gallon in the city to go with 25 mpg on the highway and a combined rating of 21 mpg. The S400 performs its shifts using a seven-speed automatic transmission that features an economy mode for improved fuel economy, but it also has a sport mode that holds each gear longer for higher revs and quicker acceleration. Mercedes says that the S400 Hybrid can accelerate from zero to 60 miles per hour in 7.2 seconds… a full three seconds slower than the S65 AMG! With BMW claiming its ActiveHybrid 7 Series can hit this same speed in just 4.7 seconds, the Mercedes-Benz S400 is no speed demon, but it sure is fun to drive when you want it to be. Unlike the S350 BlueTec, which comes standard with Mercedes’ 4Matic all-wheel drive system, the S400 Hybrid is only offered with rear-wheel drive configuration.

Considering the 2011 Mercedes-Benz S400 Hybrid is both a hybrid and a car that can double as a chauffeur’s vehicle, this full-size luxury sedan is surprisingly fun to drive. Even with its hybrid status and its 4,630-pound curb weight, this S400 felt pretty sporty along the windy roads of northern Virginia thanks to its responsive steering and the Airmatic adaptive air suspension system, and in addition to the recuperative braking system, this S400 also gets vented and cross-drilled front rotors which help the big S-Class slow down even quicker when taking on tight turns. As fun as this car can be, most drivers are likely to buy the S400 Hybrid for its fuel economy in stop-and-go city driving where the true luxury of the S-Class is apparent with a smooth ride and quiet interior, and during our trip in the heavy traffic of Washington, D.C. we consistently saw more than 20 mpg in the city.

Unfortunately, city driving is also where this hybrid system is most noticeable. Being a mild hybrid, the advantages of the system are during stops and while braking, and the S400’s system is far more discernible than in some of its competitors especially in stop-and-go driving as was the case of our trip in the heavy traffic of Washington, D.C. Take-offs are remarkably smooth, but the transition from battery to gas feels somewhat jerky when coming to a stop. It isn’t likely that buyers looking for this much luxury and technology will be bothered by the rough stops especially when factoring in the better combined fuel economy than the 7 Series hybrid and the Lexus LS Hybrid.

The 2011 Mercedes-Benz S-Class has yet to receive crash-test ratings from either the National Highway Traffic Safety Administration (NHTSA) or the Insurance Institute for Highway Safety (IIHS). The S400 Hybrid comes standard with safety features that include eight airbags, active front head restraints, daytime running lights (DRL), electronic brake-force distribution with brake assist, four-wheel anti-lock disc brake system, traction control, electronic stability control and tire pressure monitoring system (TPMS). All 2011 S-Class models come standard with Adaptive Highbeam Assist, Mercedes’ mbrace in-vehicle services and Attention Assist sounds a warning when erratic steering inputs are detected from the driver.

Over the last 10 years or so, the market for hybrid cars has grown substantially, and the 2011 Mercedes-Benz S400 Hybrid proves that even luxury automakers are looking to take advantage of this fuel-efficient technology to improve sales as well as Corporate Average Fuel Economy (CAFE) numbers. Although it is hard to think of a luxury land yacht as being in the same category as the fuel-efficient Prius, the 2011 Mercedes S400 is a perfect choice for eco-conscious buyers who aren’t ready to give up the size, opulence or technology found in the S-Class.

Pros

• excellent fuel economy for a big sedan
• elegant, luxurious interior with plenty of cabin tech
• great value compared to competition

Cons

• transition from battery to gas feels jerky when stopping
• unable to drive under all-electric power like some competitors

Mercedes-Benz provided the vehicle for this review
Photos by Jeffrey N. Ross