In August 1959, a profoundly revised passenger car range was presented. According to the motto “The New Six Cylinder Model – A Class Of Its Own” three completeley reconstructed models appeared as the successors of the fomer six-cylinder models 219, 220 S and 220 SE.
Except for some equipment details, the only difference between the new 220 b, 220 Sb and 220 SEb, which internally were allocated to model series 111, were the different types of engines.
All three models had a spacious, elegant car body, distinguished by its salient feature the fintails – a concession to the prevailing fashion, which was heavily influenced by the Americans at the time.
It was this characteristic design, which later gave the name to a whole new generation of models. The types mentioned above are today generally referred to as “fintail” models.
The new models set the standard for passive safety. For the first time, the new Barényi patent, a sturdy passenger cell and deformation zones at the front and the rear, had been realised.
Safety was the guiding principle in the design of the interior; thus the new models were fitted with an upholstered dashboard with flexible and partially recessed instruments and a steering wheel with an upholstered centre-piece; another remarkable feature were new special door locks, which further improved driving safety.
Eight features distinguished the exterior of the 220 b from its two sister models: except for the type labels, the 220 Sb and 220 SEb were identical in appearance; they had an additional chome trim on the right and the left of the radiator grill, a chrome plated air intake grid in front of the wind screen and chrome wheel caps.
The differences at the rear of the car were more pronounced: The two models with the letter “S” in the type description had a chrome trim above the rear window, a decorative trim lining the rear edge of the boot lid, bigger taillights with integrated number plate illumination and additional quarter bumpers between the taillights and the rear bumper.
The tailfins had decorative chrome trims at the rear end and along the upper edge.
The engines were basically taken from the predecessor models and had only been slightly modified. All three units were fitted with a new valve drive and a steeper camshaft.
The powerplant of the 220 b had two carburettors now and the injection engine of the 220 SEb hat been fitted with straight intake pipes. This resulted in a power increase of 4 and 5 hp respectively.
Chassis and brakes were also basically carried over from the preceding Types, the wheel suspension had clearly been worked upon, however.
The sub-frame concept, which was introduced at the time of the “ponton” models, had been retained. However, its form had changed – it now consisted of a simple transversal bar with an elastic link to the frame floor at two points.
The well-tried single joint cross shaft axle was fitted with a compensating spring, which was horizontally located above the pivot in order to ensure even distribution of axle load.
The shock absorber in the front and the rear were situated as close to the wheels as possible which did not only result in a more effective dampening of vibration but also allowed better access.
During the time of production the brakes were modified twice: In April 1962 first the 220 Sb and 220 SEb models were equipped with disk brakes at the front wheels.
The same procedure was then applied to the 220 b which was moreover fitted with a power brake that earlier had only been available at an extra cost. In the course of revision all three models were fitted with a divided brake system, which allowed safe braking, even if one brake circuit failed to function.
Like their predecessor models, the three 111 series models were available with the hydraulic automatic clutch “Hydrak”, only until the beginning of 1962. A fully-fledged automatic transmission, which had been developed for years until it was fit for serial production, was at first available for the 220 SEb only from April 1961.
However, from August 1962 it could be ordered for an additional cost of DM 1,400 for the 220 b and 220 Sb, too.
In contrast to the Borg-Warner automatic transmission, which had been used from 1956 in the 300 c and from 1957 in the successor model 300 d, Daimler-Benz’ own new construction did not have a torque converter but a hydraulic clutch, which had the advantage that power losses were low.
The secondary 4-gear planetary drive consisted of two planetary sets, three multi-disk clutchs and three belt brakes.
In August 1961, another top-class model was presented with the 300 SE. With respect to its exterior and technical concept it closely resembled the 220 SEb model but many technical specialities were included as standard.
Basic equipment comprised not only the 4-speed automatic transmission and the newly developed power assisted steering, but also air suspension, used for the first time on a Mercedes-Benz and allowing a combination of sporty handling and maximum ride comfort.
The brakes of this model, with the internal designation W 112, represented another advance: for the first time a standard Mercedes-Benz production car was fitted with a dual-circuit brake system and disk brakes front and rear.
The 3-liter injection engine was based on the tried and tested engine from the 300 d, but now had a light-alloy block and was thus approximately 40 kg lighter.
Carburation was still on the principle of intermittent inlet manifold injection using a Bosch injection pump. In January 1964 compression was raised slightly and a larger Bosch injection pump was used resulting in an increase in performance from 160 to 170 hp.
The body of the 300 SE was almost identical to that of the 220 SEb, but had more extensive chrome trim.
The most prominent distinguishing feature was the chrome strip running from the headlights to the taillights in the side ribbing; additionally, the 300 SE had trims around the wheel arches as well as a broad chrome strip below the doors.
The small “300 SE” badges integrated on the C-pillars were less dashy. If desired by the customer, this additional chrome trim could be omitted.
At the Geneva Motor Show in March 1963, the long-wheelbase version of the 300 SE was presented, identical to the 300 SE apart from the increase in length of 100 mm.
The increase in space was exclusively to the benefit of passengers in the rear with more leg-room and improved access through the wider doors. An internal partition with an electrically operated window was available as an option.
Apart from the difference in dimensions , the 300 SE and 300 SE with a long wheel-base were easily distinguishable through one feature:
The long version does not have a decorative screen in the C-pillar, since exhaust ventilation is performed differently, the openings are there missing.
Both versions, 300 SE and 300 SE long, were now also available with 4-speed manual transmission and a corresponding reduction in price of DM 1,400.
Production of the 2.2- and 3-liter models with “fintail” bodies ceased in July/August 1965. The 220 Sb, 220 SEb and 300 SE were replaced by the 250 S, 250 SE and 300 SE, which belonged to a completely new model generation.
At the same time the 220 b was replaced by the 230 S. This was in fact a new designation for an “old” model: the 230 S was largely identical to the 220 Sb, but had received a modified engine.
By giving the former 2.2-liter engine a wider bore and higher compression, performance could be boosted by 10 hp to 120 hp.
The hydro-pneumatic self-levelling suspension of the rear axle, which replaced the former coil spring and kept the body level constant independent from vehicle load capacity, was also new.
Apart from the model badge on the boot lid, there was no external difference between the 220 S and the 230 S.
By the time that production of the 230 S was discontinued in January 1968, 41,107 of them had been built, of which 341 were chassis for special bodies.
A estate version was produced by the Belgian IMA and was marketed by Daimler-Benz as the 230 S Universal.
Between 1959 and 1968 a total of 344,751 saloons and chassis of model series 111 and 112 were produced at the Sindelfingen plant.