W120 'Ponton'
The first modern mid size Mercedes was the W120 'Ponton' 180 of 1953. Sharing its engineering with the R121 190 SL of 1955, the Ponton was a stylish sedan with four-cylinder power. A larger-engined W121 190 appeared in 1958.
W110 'Fintail'
Mercedes added tailfins to both the big S-Class and the new W110 'Fintail' 190 of 1962. Straight-6 power appeared for the first time in the 1965 230 model, and the fours grew in displacement that year as well.
W114/W115 'Stroke-8'
The mid size Mercedes was redesigned in 1968 as the W114/W115 'Stroke-8'. This time, the 6-cylinder models (The W114s) were most prevalent, with the W115 line making up the bottom of the company's offerings with four - and five-cylinder power. Diesel engines joined the line-up, as did a coupé body.
W123
The popular W123 quickly became a best-seller on its launch in 1977. Especially in Diesel 240D (and later 300D) guises, the cars enhanced the company's reputation for product quality. Over 2.3 million were produced until the end of production in 1985.Saloon/Sedan, Coupé and Estate body configurations were offered.
W124
The 'E-Class' name first appeared in the USA with the face-lifted W124 in 1994 (the w124 was introduced in the US in 1986 but continued with the older models' naming convention until 1994, when all Mercedes Benz models switched to a new system, e.g., E320 instead of 300E). The 300D continued to be the fuel economy option over the 4 and 6 cylinder gasoline engines, and the gasoline V8 engines (available after 1992) increased gasoline power outputs further. The V8 powered sedans/saloons were named 400E/500E from 1992–1993, and E420/E500 after 1993. Likewise, the 3-liter cars (e.g., 'E300') where also re-badged to 'E320' with the new 3.2 litre engines and naming rationalization of 1994.
Saloon/Sedan, Coupé, Convertible and Estate body configurations were offered.
From 1992 to 1994 Mercedes offered a limited production sport version of the W124 sedan, created and assembled with help from Porsche. This was called the 500E (E500 for 1994).
W210
The W210 E-Class, launched in 1996, brought the mid-size Mercedes firmly into the upper end of the luxury market. Though six-cylinder models were still offered for a time, the four-light front end and high prices moved the car upmarket. In September 1999 the W210 E-class was facelifted. This included visual, mechanical and quality improvements over the earlier versions.
W211
Launched in 2002, the W211 E-Class was another evolution of the previous model and was considered by the motoring media as an even more competitive offering to the long term rival BMW 5-Series (which previously was the preferred choice of the motoring media). Before North American sales began, the car was shown in the 2002 movie Men in Black II.The W211-based W219 CLS-Class 4-door coupé was introduced as a niche model in 2005, primarily to attract a younger demographic.
The W211 E-Class was face lifted in 2006 to address quality and technical issues raised by earlier models, Sensotronic was dropped, while Pre-Safe (w/o brake support) was made standard. The largest factory built engine in the E-class range is the E500 (badged E550 in the U.S.) which had its engine size increased from 5 litres to 5.5 litres in 2006 along with the facelift. There is also an AMG model badged E63 AMG and other tuning house installations.
Mercedes-Benz introduced their BlueTec Diesel system to the E-Class at the 2006 North American International Auto Show as the E320 CDI BlueTec. BlueTec is a two-phase system for cleaning diesel emissions. The first phase makes the E320 CDI legal in 45 of the 50 United States (plus the District of Columbia). The second phase uses urea for further reductions to meet the more stringent standards of California, Maine, Massachusetts, New York, and Vermont. Sales of E320 CDI BlueTec began in autumn 2006 as a 2007 model, but 50-state legal models with urea injection will not be introduced until the 2009 model year.