Mercedes Benz 250 S W108
Production 1965 — 1972
(incl. 300 SEL 6.3: 6,526)
Predecessor Mercedes-Benz W111
Successor Mercedes-Benz W116
Class Full-size Luxury car
Body style(s) 4-door sedan
Engine(s) 2.5L straight-6
The Mercedes-Benz W108/W109 model series was a large luxury car line built by Mercedes-Benz from 1965 through 1972. The W108/W109 was a replacement for the higher end of the "Fintail" sedan range, with three-box styling similar to the W111/W112 coupes. The somewhat controversial fins of the so-called earlier W111"Heckflosse" were eliminated by designer Paul Bracq.
The initial lineup featured three Straight 6 engined W108 (short-wheelbase, coil-sprung suspension) models: the 250S, 250SE and 300SE. The long-wheelbase W109 featured initially just one model, the 300SEL, which was equipped with self-levelling air suspension.
In 1967, the 250S and 250SE were replaced by the 280S and 280SE. The 300SE was deleted and the 300SEL received the 280's new 2.8-litre engine.
The 6.3 engined V8 300SEL was launched in March, 1968: it used the engine first seen in the 600 model, which equipped the lighter bodied W109 for a claimed headline grabbing 0-60 mph (0-96km/h) time of 6.3 seconds. US market detoxification requirements sapped the performance a little west of the Atlantic, but the 300 SEL 6.3 was nonetheless the flagship model in the Mercedes line-up. It was deemed by many the world's best car and fastest production saloon, and held this title for many years.
By 1970 the absence of a more mainstream V8 engined version was seen as a handicap in the US market, and this gap was plugged in the W108 and W109 versions with the introduction of a 3.5 litre V8 engines, to be joined a year later by a 4.5 litre V8 destined at this stage only for the US market. By this time development of the Mercedes-Benz W116 was well advanced, and the V8 engined W108s were differentiated from the forthcoming models by retaining the 280 and 300 designations. Thus the first Mercedes Benz 350 SE would be the W116, appearing only in 1972. The short wheel base version of the W108, when fitted with the 3.5 engine, was badged as the 280 SE 3.5.
The W108/W109 vehicles carried over many of the basic engineering principles from previous models, but had many refinements to make them some of the most well equipped cars of the era. The 300SE and 300SEL were especially well appointed, featuring burled walnut dashboards, automatic transmission and power windows. The 300SEL 4.5 featured a sophisticated and advanced 4.5L V8 petrol engine, which was carried over to the W116 S-class and R107 SL roadster, as was the smaller 3.5L unit.
The standard transmission for Europe was a four-speed manual gearbox. A four-speed automatic option was also available. For the six-cylinder models only, a five-speed manual gearbox was also offered, from 1969, though few customers opted for it.
When the V8-engined cars were introduced in 1970, the default transmission was the four-speed automatic box, driven via a fluid flywheel rather than the more usual torque converter. Buyers could still opt for a four-speed manual box, however, and benefitted from a price reduction if they did so. The 4.5 litre version offered from 1971 but only in the USA, was fitted with a three-speed automatic box with a torque converter. This engine/transmission combination became more widely available when incorporated in the successor model.