The E400 will feature a 3.5-liter, V-6, rated at 306 hp and 273 lb-feet of torque, supplemented by an electric motor, which adds 27 hp and 184 lb-ft of torque. Mercedes states that the hybrid will achieve 24 mpg city, 31 mpg highway, and a combined rating of 27 mpg, based on the American CAFE standard. Those figures will likely change slightly for the official EPA ratings. As it stands, the E400 bests the E350 (EPA rated at 23 mpg combined) and the E350 Bluetec diesel (26.5 mpg combined). The Bluetec, however, squeezes out one more mpg on the highway than the hybrid.
Mercedes is calling the powertrain a modular hybrid system, which means that the additional components such as the lithium-ion batteries required no alteration to the vehicle’s chassis or body. In addition to the powertrain, the hybrid features a number of fuel-saving tech such as start/stop technology, low-resistance tires, and regenerative braking. The press release also mentions “purely electric motoring” and a “sailing” function, although no technical details were disclosed. Also missing from the release are performance figures and pricing.
Also debuting at the Detroit show is the E300 Bluetec hybrid, powered by a four-cylinder diesel rated at 204 hp and 369 lb-ft of torque; it’s supplemented by the same electric motor as the E400. Mercedes will launch the E300 in Europe sometime next year for Europe only, with no immediate plans to sell it in the U.S. According to a spokesperson from Mercedes-Benz USA, the E400 should arrive in U.S. showrooms during the second half of 2012 before continuing on to other markets such as Japan and China.