Mercedes-Benz released first pictures of their new W221 S-Class sedans in June 2005 and announced that they will go on sale in Europe in autumn 2005 as the 2006 model and early in 2006 in the US as the 2007 model. The North American introduction for the W221 was at the Los Angeles Auto Show in January, 2006, with the S550 and S65 AMG introduced at the 2006 North American International Auto Show.
The new Mercedes S-Class is slightly larger than its predecessor W220, and it will be available in two body lengths - 5076 or 5206 mm, which is 33 and 43 mm more than the previous S-Class. The wheelbase has increased by 70/80 mm to 3035 and 3165 mm. The body is also 16 mm wider and 29 mm higher than those of the previous model. The W221 features a more luxurious, Maybach-like appearance, as well as three newly developed engines with up to 26 percent power increase. The interior is also completely new, all materials have been upgraded and the center-mounted transmission has been replaced with a column-shifter.
Three of the four engines available for the new S-Class are newly developed and they generate up to 26 percent more output and up to 15 percent more torque. The models equipped with the V6 and V8 engines will feature a seven-speed automatic transmission 7G-TRONIC as the part of standard equipment. 4MATIC four wheel drive will become available at a date to be determined. One major mechanical change is the elimination of brake by wire technology in favor of conventional hydraulic power assist. The brakes continue to become more advanced, however, with the new Brake Assist Plus system monitoring for an impending collision and increasing braking if needed, while the Distronic Plus cruise control is meant to bring the car to a complete stop. On November 27, 2005, the British television show Top Gear showed a video clip of a demonstration at Mercedes’ factory: the S-Class vehicle rear-ended a parked car in front, the Distronic feature not functioning in heavy fog.
Three of the four engines available for the new S-Class are new developments by Mercedes-Benz. They generate up to 26 percent more output and up to 15 percent more torque. In addition to the 3.5-litre V6 engine with 272 hp, a new eight-cylinder unit developing 388 hp and a muscular 390 lbs-ft of torque from a mere 2800 rpm upwards will already be available at the time of the market launch in autumn 2005. It accelerates the S 500 from standstill to 62mph in just 5.4 seconds. From the first quarter of 2006 Mercedes-Benz will be extending the range of engines for the S-Class with the new V6 CDI engine, which has a particulate filter as standard in certain countries. This direct-injection unit has an output of 231 hp and generates a maximum torque of 398 lbs-ft from 1600 rpm. This means that the new S 320 CDI betters the preceding model by 13 percent in output and eight percent in torque. The output of the twelve-cylinder engine in the top-of-the-range S 600 (available from the first quarter of 2006) has increased to 517 hp, while torque has increased by just under four percent to a remarkable 612 lbs-ft from 1900 rpm. As standard equipment, the V6 and V8 engines for the new S-Class are combined with the unique seven-speed automatic transmission 7G-TRONIC.