Unimog 401
Unimog 401 | |
---|---|
401 | |
Overview | |
Type | Tractor |
Manufacturer | Daimler-Benz AG |
Also called |
Unimog Unimog U25 |
Production | 1951–1956 |
Assembly | Mercedes-Benz-Werk Gaggenau |
Body and chassis | |
Related | Unimog 402 |
Powertrain | |
Engine |
OM 636 (Diesel, 18.5 kW) |
Transmission | 6-speed manual with 2 additional reverse gears |
Chronology | |
Predecessor | Boehringer Unimog 70.200 |
Successor | Unimog 411 |
The Unimog 401 is an all-wheel-drive vehicle of the Unimog-series by Mercedes-Benz, which is due to its construction both a tractor and equipment carrier. It was produced by Daimler-Benz in the Unimog plant in Gaggenau from 1951 to 1956; 16'250 Unimog 401 and 402 were made.[1] Initially, the Unimog 401 was made in the Cabrio version only. The closed cab model Froschauge (German for frog-eye), with a cab made by Westfalia,[2] was introduced in September 1953.[3] An increased wheelbase model of the 401 was made, it has the model number 402. Both Unimog 401 and 402 were succeeded by the Unimog 411, that was available as a long and as a short wheelbase model.[2]
History
After World War II, German engineer Albert Friedrich built the Universalmotorgerät, however, Daimler-Benz did not want to put it into series production. Boehringer in Göppingen on the other hand was interested and produced a prototype for the 1948 DLG-exhibition in Frankfurt. The Unimog was of high interest, so Boehringer decided to start the series production. Until 1950, approximately 600 Unimog 70.200 were made, their brand logo was an ox-head with U-shaped horns. In late 1950, Daimler-Benz purchased Boehringer with all their employees. The production was moved to Gaggenau and Daimler-Benz started the series production in May 1951.[4] Initially, the Unimogs model number was 2010, it was changed to 401 in 1953. The Unimog 401 was the first Unimog to receive the Mercedes-star.[5]
Technical description
The Unimog 401 is a very compact vehicle with an approximate length of just 3.5 metres. It has an U-shaped ladder frame, rigid portal axles both in the rear and front with four wheels of the same size. Each axle has additional reduction gears for each wheel built in. Both front and rear axle are supported by a central joint and panhard rods. The 401 has coil springs and hydraulic shock absorbers. Daimler-Benz used 6.5–20" multi-purpose tyres for the Unimog, that are made for both on- and off-road applications. The brake system is hydraulic, the 401 has drum brakes for each wheel.[6] While the 401 has a wheelbase of 1720 mm, the 402 has 2120 mm wheelbase.[2]
Engine and gearbox
The engine of the 401 is a car engine, type OM 636 VI. This engine is a water-cooled naturally aspirated straight-four-diesel with precombustion chamber injection, OHV-valvetrain and a displacement of 1767 cm3. Its standard power output is 40 PS (29.4 kW), this figure was reduced to 25 PS (18.4 kW) at 2350 min−1 for the Unimog. The OM 636 is mounted slightly inclined towards the rear, in the front of the Unimog. It has an electric starter.[6]
The Unimog 401 has a Daimler-Benz six-speed constant-mesh gearbox with two additional reverse gears. It has a clutch-independent switchable all-wheel drive and differential locks for the front and rear axle. The clutch is a Fichtel & Sachs single-disc-dry-clutch.[6] Daimler-Benz offered an additional two-speed crawler-gearbox as a factory option.[7]
Features and accessories
The 401 has a 150 W Bosch alternator, a 12 V / 105 Ah lead-acid battery, two headlights, two rear lamps, electric trafficators, windscreen wipers and a horn. A plug socket for a trailer was offered as a factory option.[6]
A flatbed is mounted on the rear part of the Unimog, it measures 1500 × 1500 mm and is designed for a payload of 1000 kg. The 401 has a spring-mounted hitch in the rear and a standard hitch in the front. For additional equipment, it has an anchor rail.[6]
For power take-off, the Unimog was available with front and rear PTOs (DIN 9611, 540 min−1). The rated power is approximately 22 PS (16.2 kW). A 315 mm belt pulley was also available, the ouput power is 22 PS (16.2 kW) as well. Daimler-Benz also offered a spare wheel, rear twin tyres, a trailer-brake-system, a winch, a mowing bar and air compressors for the 401.[7]
The initial Unimog 2010 was offered as a Cabrio with a foldable top, a conceiling windscreen, removable side windows and a rigid rear panel. It was available in the colour Unimog-grün. After the re-badging, the closed cab was offered. The Cabrio version was now called Version A while the cab-version was called Version A/F. Unimogs with a trailer-brake-system were called Version B and Version B/F. Unimogs with a closed cab were available in the paint colours Unimog-grün, hellgrau and Mercedes-blau.[7]
Technical data
Unimog 401[6] | |
---|---|
Measurements and weights | |
Track width | 1270 mm 1470 mm (after switching wheels) |
Wheelbase | 1720 mm |
Ground clearance | 380 mm |
Length | 3520 mm |
Width | 1630 mm |
Height | 2050 mm (with foldable top) |
Turning clearance circle diameter | 7600 mm |
Bed | 1.5 × 1.5 m, 2.25 m2 |
Mass | 1680 kg |
Payload | 1000 kg |
max. allowed mass | 3150 kg |
Drive train | |
Torque transmission to | rear wheels, switchable all-wheel drive |
Gearbox | Daimler-Benz six-speed constant-mesh gearbox, two reverse gears |
Clutch | Single-disc-dry-clutch by Fichtel & Sachs |
Top speed | 53 km/h |
Fuel consumption | 10 l/100 km |
Engine | |
Type | OM 636 VI |
Layout | Straight-four diesel with precombustion chamber injection, OHV-Valvetrain |
Cooling system | Water |
Bore × Stroke | 75 × 100 mm |
Displacement | 1767 cm3 |
Compression ratio | 19 : 1 |
Rated power | 25 DIN-PS (18.5 kW) at 2350 min−1 |
Max. torque | 10.3 kp·m (101 N·m) at 2000 min−1 |
Bibliography
- Werner Oswald: Mercedes-Benz Lastwagen und Omnibusse 1886–1986. Motorbuch Verlag Stuttgart, 2008, ISBN 978-3-613-02943-9.
References
- ↑ Werner Oswald, p. 320.
- 1 2 3 Unimog-Community: Unimog U 401 (in German)
- ↑ Werner Oswald, p. 321.
- ↑ Werner Oswald, p. 321.
- ↑ Unimog U 2010 – Unimog-Community (in German)
- 1 2 3 4 5 6 Daimler-Benz AG: Technische Daten Unimog 401 1955 (in German)
- 1 2 3 Daimler-Benz AG: Preisliste für Unimog 401 1955 (in German)
Unimog, a range of trucks by Daimler AG, road vehicle timeline, 1950s–present | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Type | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |
Traditional | 2010 | 401 | 411 | 411a/b | 411c | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
402 | 404 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
406/416 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
421 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
403/413 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
LBU | 407 | 408 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
MBU | 417 | 418 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
424 | 427 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
SBU | 425 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
435 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
437 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
UGN | 405 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
UHN | 437.4 |