Successful models and a performance boost.

At the DLG exhibition in Hannover in 1956, Daimler-Benz presented the Unimog series 411 as the successor to the 401/402 series. Main feature: more power. The 30 hp provided the decisive extra to meet the growing demands in agriculture. But comfort was not neglected: alongside improved seats, reinforced shock absorbers were used on the 411 series.

As with the previous model, a short and a long wheelbase version were available from the factory. The latter proved extremely popular because from 1957 it could be fitted with a newly developed cab. The all‑steel cab offered significantly more space than before and stood out with Daimler-specific features and a rounded-edge design that set standards in the commercial vehicle sector.

Because of its agility, its comparatively high speed and its very good off-road capability, the Unimog was increasingly used for transport tasks. The power take-offs (PTOs) available at the front and rear gave users ideal conditions for the flexible use of saws, pumps, winches and other equipment.

Due to its outstanding off-road capabilities, for which even approach and departure angles of 45° at the front and rear were no problem, armies also became increasingly interested in the Unimog from the mid-1950s. With the Unimog S (model series 404) a vehicle was created that met their high demands. The Unimog S had a large cargo area that could be realized either as a flatbed or as a box body. Unlike Unimogs used in civilian service at that time, it relied on high-horsepower petrol engines.

The numerous variants of the Unimog S were produced in Gaggenau until 1980 – with 64,242 vehicles this model series remains the most successful to date. Thus, the 404 series was also very popular with fire departments.

The continuous improvement of the vehicle and its components kept advancing the Unimog. Following the motto: evolution rather than revolution. Thus, from the late 1950s more powerful compressed-air brakes were introduced, the steering was improved, and a hydraulic lift was fitted. In 1959 there was a genuine first in the commercial-vehicle sector: the fully synchronized 6-speed transmission, which had already been fitted as an optional extra in the Unimog 411 since 1957, became standard equipment. It made gear changes not only more comfortable than the previously used dog‑clutch gearbox, but also more efficient. On request, multi-stage crawler gear transmissions were also available for Unimog.

At the DLG exhibition in 1962, Daimler-Benz once again unveiled a Unimog. With the Unimog series 406 the "heavy series" was introduced, featuring a widened track and a longer wheelbase to meet the demand for ever larger and more powerful agricultural machines. The detuned diesel engine delivered 65 PS, but was designed so that it could provide this power continuously under full-load operation. Later, more powerful engines with up to 110 PS followed.

With a top speed of 65 km/h the Unimog series 406 was perfect for use as a road tractor. On the other hand, it could be operated in creep gear at just 0.03 km/h. A range that left little to be desired.

Comfort in the driver's cab also increased with the series 406. For the first time there were padded and adjustable driver's seats. The cab's ergonomics also made long working days as comfortable as possible. This made the versions with an all-steel cab particularly popular members of public works fleets in towns and municipalities. But the Unimog's heavy series also established itself very quickly with construction companies and in industry.

With the model series developed and produced in Gaggenau from the mid-1950s, the Unimog was able to establish itself as a true long‑running success on the market. With the introduction of the heavy series, the Unimog range evolved into a comprehensive programme. Not only in its core segment, agriculture, but also in many other sectors thanks to its high flexibility and performance.

The secret of its success: a compelling vehicle concept that has been consistently maintained and continuously and ingeniously refined technically. The high quality of the model series produced over many decades is evident not least in the fact that some of the vehicles are still in service today.