Mercedes-Benz

At the 1965 Internationale Automobil-Ausstellung in Frankfurt, the W108 and W109 were presented as the successor to the Heckflosse series. The initial model range consisted of the 250 S, 250 SE and 300 SE (W108) and a long-wheelbase 300 SEL (W109), all of them fitted with six-cylinder engines. Compared to the Heckflosse, the W108 had a lower body waist line and increased glass area. The result was a visibly newer-looking, sleeker car with an open and spacious interior. The W109 not only had a longer wheelbase, but was also more luxuriously appointed, featuring a burled walnut dashboard, automatic transmission and power windows along with an optional air conditioning system. 

1965

To coincide with the launch of new, cheaper W114/115 models, the inline-six engine range was revised in November 1967. The 2.5-litre engine was enlarged to 2,778 cc, giving way to the 280 S and SE. At the same time, the standard wheelbase 300 SE was dropped, while the 300 SEL obtained a smaller 2,778 cc engine with higher output. In 1966, company engineer Erich Waxenberger took the powerful 6,332 cc V8 engine from the Mercedes-Benz 600 and put it into the engine bay of the 300 SEL. The result was an impressive level of performance, making it the fastest production sedan of its time. The company turned the prototype into the 300 SEL 6.3, introduced at the Geneva Motor Show in March 1968. In August 1969, the 300 SEL 3.5 was introduced, followed by the 280 SE, SEL 3.5 in July 1970. The 300 SEL 2.8 was dropped in January 1970 since the 300 SEL 3.5 was selling better and had better performance. The production of the 280 SEL ended in April 1971, leaving 280 S and 280 SE as sole models with six-cylinder inline engines until the end of production in 1972, following the introduction of the new S-class W116.