• W 111/112 series
• W 108/19 series

Mercedes-Benz 220 b, 220 Sb, 220 SEb, 230 S, 300 SE, 300 SEL, W 111/112 series (1959 to 1968)
In August 1959, the company announced a thoroughly revised passenger car range. Under the slogan: “The new six-cylinders – in a class of their own” and as successors to the existing six-cylinder models came the following three completely re-designed models – the 220 b, 220 Sb and 220 SEb of the W 111 series.


In addition to various differences in equipment detail, the three new models also differed in terms of their engines. A coupe version of the 220 SEb arrived in February 1961, and a convertible followed in September that same year.

What the three saloons had in common, however, was an exceptionally spacious and elegantly styled body, the most distinctive features of which were its tailfins – a concession to the American influence on contemporary tastes. This characteristic design element would later give rise to the name by which the entire model generation came to be known – today the generic term “fintail” is applied to all these models. The new model series set new standards in terms of passive safety, for these were the first production cars to feature the Barényi-patented rigid passenger cell with front and rear crumple zones. Safety was also given top priority in the design of the interior. The new models had a padded instrument panel, for example, with yielding and in part recessed controls, as well as a steering wheel with padded boss. Also worthy of note was the first use in this form of safety door locks, likewise major contributors to safety in the case of accident.


From the purely external point of view, the 220 b differed in eight features from its two sister models. The 220 Sb and 220 SEb, which were identical on the outside with the exception of the model designation, each had an additional chrome strip to either side of the radiator grille, a chrome-plated air intake grille in front of the windshield, and chrome-plated wheel trim. At the rear the differences were rather more apparent. The two models with the “S” in their model designation had a chrome strip above the rear screen, an ornamental moulding to round off the trunk lid, larger rear lights with integrated license plate lamps, as well as additional bumper horns between the rear lamps and rear bumper. In addition, the tailfins – officially known as “guide bars” – had ornamental mouldings not only to the rear end-piece but also to the upper edge.

Tried-and-tested engines
The engines were to all intents and purposes the same as those of the predecessor models but with minor modifications. All three units had modified valve control linkage and a steeper camshaft. The 220 b engine was now fitted with two carburettors and delivered 95 hp (70 kW), 110 hp (81 kW) in the 220 Sb. The direct injection unit for the 220 SEb featured straight intake pipes and developed 120 hp (88 kW).


The running gear and brake system also largely came from the predecessor models, although the suspension had been thoroughly revised in certain respects. At the front, the subframe design introduced with the ponton-type models was retained, although the shape was modified to a simple cross-member design joined flexibly to the frame floor at only two points. At the rear, the tried-and-tested single-joint swing axle was fitted with a compensating spring, positioned horizontally above the pivot point in order to distribute axle load equally to both drive wheels. The shock absorbers on the front and rear wheels were now positioned right on the outside, a measure that not only provided more effective vibration damping but also improved accessibility.

During the production period the brake system underwent two modifications. First the 220 Sb and 220 SEb were equipped with disk brakes to the front wheels in April 1962. Then in August 1963 the same modification was added to the 220 b and the model was simultaneously equipped with a brake booster – a feature available up until that point only at extra cost. As part of these changes, all three models were also fitted with a dual-circuit brake system, which offered safe retardation of the vehicle even when one of the circuits failed.

“Hydrak” hydraulic-automatic clutch
As with their predecessor models, the three new W 111 models were also optionally available with the “Hydrak” hydraulic-automatic clutch, although only until early 1962. After years of in-house development to reach production standard, a fully fledged automatic transmission was ready for use from April 1961, initially in the 220 SEb only, and then also from August 1962 upon order with the 220 b and 220 Sb – at an extra cost of DM 1,400. Unlike with the Borg-Warner automatic transmission available with the 300 c from 1956 and the 300 d successor model from 1957, the company’s own design did not use a torque converter, but instead relied on a hydraulic clutch. This had the advantage of reducing power loss. The downstream four-speed planetary gear train consisted of two planetary gear sets, three multi-plate clutches and three band brakes.

A new top-of-the-range model
In August 1961 the 300 SE was introduced as the new premium-class model, a vehicle which in terms of its external appearance and technical design lent heavily on the 220 SEb, but which also included numerous technical tidbits as standard. Coupe and convertible made their debut in February 1962. In addition to the four-speed automatic transmission and the likewise newly developed power steering, basic equipment also included air suspension – a first for a Mercedes-Benz passenger car – which offered a combination of sporty handling with top-quality ride comfort. The brakes represented a further innovation in the model bearing the internal designation W 112, since this was the first Mercedes-Benz production car to be equipped with a dual-circuit brake system as well as disk brakes at the front and rear wheels.


The 3.0-liter direct injection engine was based on the tried-and-tested unit used in the 300 d model, but it featured a light-alloy block with pressed-in cylinder liners and was approximately 40 kilograms lighter as a result. As with the predecessor model, mixture preparation was achieved using timed manifold injection with a Bosch two-plunger injection pump. In January 1964, the compression was raised very slightly and the injection system converted to a Bosch six-plunger injection pump. This permitted engine output to be increased from 160 hp (118 kW) to 170 hp (125 kW).


The body of the 300 SE was almost identical to that of the 220 SEb, but it offered more in the way of chrome trim. The most distinctive difference was the chrome strip in the lateral beading that ran from the headlamps to the rear lights; in addition, the 300 SE featured trim around front and rear wheel arches as well as a broad chrome strip beneath the doors. Less striking, perhaps, were the additional small “300 SE” plates integrated into the ornamental mouldings on the C-pillars. The 300 SE was also optionally available without these decorative elements.

The advent of the long version
At the Geneva Motor Show in March 1963, the company introduced the long 300 SE version, which apart from its 100-millimeter longer wheelbase, was identical to the basic 300 SE model. The extra space served exclusively to increase legroom in the rear and the entry width for the rear doors. The long 300 SE was also optionally available with partition wall and electrically operated dividing screen. Apart from the difference in length between the 300 SE and the long 300 SE, an additional equipment detail made it easy to distinguish between the two cars: The long version had no ornamental moulding on the C-pillar since the through-flow ventilation was designed differently and there were therefore no vents. With effect from the introduction of the long-wheelbase version, both variants, the 300 SE and the 300 SE long, were also available with four-speed manual transmission; this reduced the sale price by DM 1,400.

In July/August 1965 production came to an end for the 2.2-liter and 3.0-liter models with “fintail” bodies. The successor models were the 250 S, 250 SE and 300 SE, which collectively belonged to an entirely different model generation. At the same time, the 220 b was replaced by the 230 S. In spite of the unusual model designation, the new model was basically a familiar face: The 230 S was to all intents and purposes identical to the 220 Sb, though with a revised engine. By boring up the tried-and-tested 2.2-liter unit and increasing the compression, output was raised by 10 hp (7.4 kW) to 120 hp (88 kW). Another new feature was the hydropneumatic compensating spring on the rear axle, which replaced the coil spring used up to that point and ensured a constant body height regardless of the size of the load. From the outside it was impossible to distinguish the 230 S from the 220 Sb – other than by casting a glance at the model designation on the trunk lid.


Even though the 230 S had something of the character of an end-of-line model from the outset, a total of 41,107 units were built prior to the discontinuation of production in January 1968, 341 of which were chassis for special bodies. One special version of the 230 S should not go without a mention: A station wagon, which was built at the Belgian firm of coachbuilders IMA on the chassis of the 230 S and sold through the Daimler-Benz sales organization from August 1966 onwards under the model designation “230 S Universal”.
Between 1959 and 1968 the Sindelfingen plant turned out a total of 344,751 saloons and chassis for the W 111 and 112 model series.

The W 111/112 series in the press
Autocar, England, November 6, 1959, on the Mercedes-Benz 220 SE: “In summary the 220 SE has outstanding road manners, undoubtedly allied to the firm’s long experience in racing. In addition, it permits the achievement of high and sustained cruising speeds with very good economy. The interior is planned to carry five people and their luggage over long distances, in a manner matched by few other cars, irrespective of their country of origin.”

Sports Cars, England, December 1959, on the Mercedes-Benz 220 S and 220 SE:
“’Fabelhaft’ is the German word for fabulous and this about sums up the new W 220 Mercedes. It sets a new standard for the industry, a standard that few manufacturers will be able to equal.”

Auto, Motor und Sport, Germany, volume 19/1963, on the Mercedes-Benz 300 SE:
“The 300 SE also operates as a kind of signboard for the Daimler-Benz car range, combining in one vehicle every design refinement available: Air suspension, automatic transmission, power steering. … There are few cars in the world in which one can travel in such comfort and safety as in the 300 SE.”
Mercedes-Benz 250 S – 300 SEL 6.3, W 108/109 series (1965 to 1972)
The new premium-class model generation consisting of the 250 S, 250 SE and 300 SE were presented in August 1965, establishing succession to the 220 Sb, 220 SEb and 300 SE fintail models. All three models shared a body designed by Paul Bracq, whose clean lines dispensed with all fashionable excess and whose restrained elegance has timeless appeal even today. In terms of their engineering design, the new models were based to a large extent on their predecessors. Other than the body, however, new features also included the two 2.5-liter engines, which were developed by increasing the bore and lengthening the stroke of the corresponding 2.2-liter units. Now the crankshaft was mounted on seven bearings, and an oil-water heat exchanger guaranteed improved heat load in the oil system. In the direct-injection version a six-plunger injection pump now replaced the two-plunger pump. In contrast to its predecessor model, however, the new 300 SE was no longer fitted with air suspension. Instead, as with the two 2.5-liter models, it had a hydropneumatic compensating spring on the rear axle, which replaced the familiar coil spring and ensured a constant body height regardless of the load.


In March 1966 the model range was expanded to include the 300 SEL, which had a 100-millimeter longer wheelbase compared with the basic model, the extra space serving exclusively to increase legroom in the rear and the entry width of the rear doors. As with its direct predecessor with the same model designation, the new 300 SEL featured air suspension as standard. Internally the models with conventional suspension were grouped under the W 108 model series, the air-sprung 300 SEL however was given its own series with the designation W 109.

Two special variants
In 1966 and 1967 two very special variants of the 300 SEL were built in Sindelfingen, never intended for series production and specially developed for the Vatican. In June 1966 a landaulet with normal wheelbase was built, which differed from the series saloon in that it had only a single seat at the rear and a landaulet soft-top that stretched to the front edge of the rear doors. Almost a year later, in May 1967, the landaulet was joined by two identical six-seater saloons, which were built on a floor assembly that had been lengthened by 650 millimetres and boasted modified rear doors as well as two folding seats in the rear. The landaulet was intended as a second vehicle for use alongside the Mercedes-Benz 600 by His Holiness himself, whereas the two Pullman saloons were to be used for transporting Vatican guests.


Production of the 250 SE and 300 SE models came to an end at the start of 1968, with the introduction of the two successor models 280 S and 280 SE in January. These differed from their predecessors only in terms of their engines and certain equipment details. The newly-developed 2.8-liter six-cylinder engine delivered 140 hp (103 kW) in the carburettor version, and 160 hp (118 kW) with direct fuel injection. Likewise from January 1968 onwards, an output-enhanced version of the injection engine giving 170 hp (125 kW) was fitted not only to the 280 SL, but also to the 300 SEL, where it replaced the 3.0-liter light-alloy engine in service to that point.

The top-of-the-range Mercedes-Benz 300 SEL 6.3
March 1968 saw the introduction of the top-of-the-range 300 SEL 6.3, featuring the V8 engine and automatic transmission of the Mercedes-Benz 600 and hence with the performance potential of a top-class sports car. Its presentation at the Geneva Motor Show caused a sensation, especially as there had been no announcements made prior to the event. The 6.3’s only distinguishing external features were its wider tires, double halogen headlamps and an additional set of high beams. The engine delivered 250 hp (184 kW), but of greater significance perhaps was its mighty torque of 51 mkg (500 Newton meters), which took the saloon from 0 to 100 km/h in 8 seconds and gave the car a top speed of 221 km/h. Although the 6.3 cost over DM 10,000 more than the 300 SEL and was more than double the price of the 280 SE, the Mercedes-Benz 300 SEL 6.3 was the object of comparatively lively interest and unit numbers totalled 6,526.


In fall 1969, the 300 SEL with the 2.8-liter six-cylinder engine was replaced by the 300 SEL 3.5, whose power unit – a completely new design – was a “small” V8 engine with 3.5-liter displacement and 200 hp (147 kW). From March 1971 onwards this engine was also used in the 280 SE 3.5 and 280 SEL 3.5 which had conventional steel springs. The 280 SE with six-cylinder engine was also still available, but the 280 SEL was removed from the range in preference for the eight-cylinder model. In parallel to the 3.5-liter V8 engine, there was also a more powerful variant with 4.5-liter displacement built exclusively for the North American market. This was delivered from May 1971 in the 280 SE 4.5, 280 SEL 4.5 and 300 SEL 4.5 export models.

One special model variant in the W 108/109 series not available on the free market was built in 1971 – the armoured version of the 280 SEL 3.5. No armoured vehicles had been produced at Daimler-Benz since the bullet-proof Mercedes-Benz 600 Pullman saloon in June 1965, but suddenly there were requests from various federal agencies to develop such a variant. As a result of the attacks carried out on diplomats in Latin America in 1970 the Foreign Ministry was obliged to give special protection to the official cars of some of its mission chiefs. The result of these measures was the armoured 280 SEL 3.5 model, of which 28 units were built between May 1971 and September 1972 and delivered to West German foreign missions in hot spots.


Production of the highly successful W 108/109 series came to an end in September 1972. In total 383,341 vehicles were built. Their successor was the W 116 series, the first models to be given the name S-Class.

The W 108/109 series in the press
Auto, Motor und Sport, Germany, issue 2/1966, on the Mercedes-Benz 250 SE: “The ease, quietness and gentleness when driving, the handling safety at high speeds and on cornering, the outstanding interior equipment, the attention to quality and design paid even to secondary details speak for themselves and rank the 250 SE well up with the worlds best cars.”

Auto, Motor und Sport, Germany, volume 6/1968, on the Mercedes-Benz 300 SEL 6.3: “We took delivery of one of the closely guarded first units, a vehicle not yet even fitted with the “6.3” designation. The lack of model badge seemed to cause confusion to many a Porsche 911 and 911 S driver, normally accustomed to being kings of the motorway and who now suddenly found themselves being left looking flat-footed by the distinguished and relatively harmless-looking Mercedes. Should any of them be reading this, we would wish to point out that they have no cause to return their vehicles to the factory on account of deficient performance.”

Source: Daimler AG