The Unimog 404, also called the Unimog S and Unimog 404 S, is a vehicle of the Unimog-series by Mercedes-Benz, produced in the Unimog plant in Gaggenau from 1955 to 1980. Marketed as Unimog U82, and later Unimog U110, a total 64,242 units of the two Unimog 404 types 404.0 and 404.1 were built, which makes the 404 the Unimog model with the highest production figure of all Unimogs. Unlike the Unimog 401, the 404 is rather a small 1.5-tonne-offroad-truck than an agricultural vehicle. In Germany, it was a common military vehicle and fire engine, 36,000 Unimog 404 were made for the Bundeswehr.
The first Unimog 404 concept-vehicle was made in 1953 and was slightly smaller than the series production model, it had a track width of and a wheelbase of . Two prototypes for the French army followed in 1954, the first 1,100 series production models were also purchased by the French army. Since the French army did not want the spare wheel to occupy space for soldiers on the bed, the Daimler-Benz engineers decided to build the Unimog 404 with a downswept frame so the spare wheel could be mounted underneath the bed. This constructional feature also allowed more torsional flexing and, therefore, improved the offroad capabilities of the Unimog. Later, the downswept frame became a key constructional feature for the following Unimog types.Carl-Heinz Vogler: ″UNIMOG 406 – Typengeschichte und Technik. Geramond. München. 2016. . Page 45. (In German)
At its introduction in 1955, the Unimog 404.1 was available as the wheelbase model with the Otto engine M 180 producing . In 1956, the wheelbase model of the 404.1 followed, available with the same engine. Both were sold as Unimog U82. The production of the U82 with the short wheelbase was stopped in 1971, while the long wheelbase model was built until 1980. Starting from 1971, the Unimog 404.0, sold as Unimog U110, was offered. It was fitted with the cab of the Unimog 406 and soon afterwards, with the model 404.012, it received the M 130 engine. However, only 1,791 404.0 were made. Also, 81 Unimog 404 were made with the diesel engine OM 615 () for the Portuguese market.
Technical description
The Unimog 404 is a small four-wheel offroad capable truck designed for a payload of . Like other Unimogs, it has a ladder frame, two portal axles with reduction gears and coil springs with hydraulic shock absorbers for the rear and front axle. All four wheels and tyres have the same size and are fitted with hydraulic ATE drum brakes. The 404 is a rear-wheel-drive vehicle with switchable all-wheel-drive and additional differential locks.
A water-cooled straight-six Otto engine, type M 180 II-U, displacing powers the 404.1. It is fitted with a Zenith 32 NDIX offroad-carburettor and transmits the torque to a fully synchronised manual Daimler-Benz-six-speed-gearbox with two additional reverse gears. As clutch, the Fichtel & Sachs K 16 Z single-disc-dry-clutch is used.
The 404 was available both with a standard closed two-door-cab and as a two-door-cabriolet with a convertible top. The 404.1 has a divided windscreen, while the 404.0 with the cab of the Unimog model 406 has a single windscreen. Only the standard cab models have side windows in the doors. Special purpose vehicles, such as fire engines, were also made with an extended four-door-cab.
Overview of the 404-series + Types of the Unimog 404Type number404-typeProduction periodCabWheelbase (mm)Engine power (kW)Engine typeNumber manufacturedNotes404.010404.0 Cabrio 2900 81 M 130 113 Cab of the Unimog 416, some units with M 180, 60 kW404.011404.0 Closed cab 2900 81 M 130 1151 Cab of the Unimog 406404.012404.0 Cabrio 2900 81 M 130 7 Cab of the 416404.013404.0 Closed cab 2900 81 M 130 520 Cab of the 406404.111404.11955–1956 Cabrio 2670 63 M 180 1210 Including 578 pre-series models, some units with 59 or 60 kW.404.112404.1 Cabrio and closed cab 2900 60 M 180 185 404.113404.1 Cabrio and closed cab 2900 60 M 180 8106 Some vehicles with 68 or 81 kW404.114404.11956–1980 Cabrio, chassis only and double cab 2900 60 M 180 50321 Some vehicles also with 68 kW404.115404.1 Closed cab 2900 60 M 180 2548 Some vehicles also with 68 kW404.117404.11969–1970 Cabrio 2900 44 OM 615 81 Model for the Portuguese market
Technical data
Type404.1404.0Sold asU82 (short)U82 (long)U110Years1955–19711956–19801971–1980Mass (approx.) 2900 kg 2970 kg 2970 kgLength 4600 mm 4925 mm 5025 mmWidth 2130 mm 2140 mm 2130 mm Height 2190 mm 2190 mm 2250 mm Wheelbase 2700 mm2900 mm Track width1630 mm Ground clearance 400 mm Bed length 2700 mm3000 mm Bed width2000 mm Bed height500 mm Fuel tank capacity2 × 60 l Tyres10–2010.5–20 Engine modelM 180/II UM 130 Engine typeStraight-six Otto, water-cooled Fuel systemCarburettor type Zenith 32 NDIXDisplacement2195 cc 2778 cc Bore × stroke80 mm × 72.8 mm86.5 mm × 78.8 mmCompression ratio7:1 Rated power (DIN 70020) at 4850 rpm at 4800 rpm Max. torque (DIN 70020) at 3200 rpm Top speed6th gear: 95 km/h1st gear: 7 km/h2nd gear: 13 km/h3rd gear: 24 km/h4th gear: 44 km/h5th gear: 72 km/h6th gear: 95 km/h1st reverse gear: 6 km/h2nd reverse gear: 10 km/h 6th gear: 100 km/h Climbing capability1st gear: 70%2nd gear: 45%3rd gear: 23%4th gear: 11.5%5th gear: 6.5%6th gear: 3.5%Source
Production figures
Year Production figures 1955 578 1956 1334 1957 2337 1958 2651 1959 3649 1960 5516 1961 4986 1962 6593 1963 5810 1964 4710 1965 4765 1966 4479 1967 2438 1968 3261 1969 3337 1970 2645 1971 802 1972 684 1973 1090 1974 932 1975 347 1976 334 1977 142 1978 53 1979 758 1980 11 Sum 64242
Bibliography
Carl-Heinz Vogler: Typenatlas Unimog. Alle Unimog-Klassiker seit 1946 bis 1993. GeraMond, München 2015, , S. 41 ff.
References