Strikingly compact and maneuverable: the O 322, purely an urban bus

Oct 30, 2008
  • Breaching the gap to the modern day and age
  • Capacity of 100 passengers
  • Innovative all-air suspension
In the chain of great bus developments by Mercedes-Benz, the O 322 can be considered an important link between two outstanding vehicle generations. Taken by itself, the Mercedes-Benz O 322 built beginning in August 1960 may not have been the big success, with 959 units being produced between 1960 and 1964 – the
Mercedes-Benz O 321 H and later on the O 302 outshone it, each with five-digit production figures. And a third successful bus also played a major role in this period: the regular-service bus Mercedes-Benz O 317.
But as link between the roundish buses of the 1950s and the up-to-date, spacious passenger haulers with rear-mounted engines, the O 322 had an important function. Around 1960, urban regular service buses frequently were still variants of large multifunctional model series including regular-service buses and touring coaches, as documented by the respective models of the Mercedes-Benz O 321 H beginning in 1954 and its successor, the O 302, beginning in 1965. In between, however, there were the specialists like the O 317 of 1958, a pure regular-service bus with a horizontal engine between the axles. One year later, at the Frankfurt International Motor Show in September Mercedes-Benz showed another urban bus, the O 322, which went into production in August 1960. With an overall length of just under ten meters and a wheelbase of 5.1 meters, the O 322 was designed as a decidedly compact and maneuverable bus. In the rear of the bus a vertically installed, lightweight in-line six-cylinder from the 300 engine series purred. Initially, its output was 110 hp, developed from a displacement of only 5.1 liters.
Clearly structured body
The O 322 basically featured the same outer shape as the O 317. The large divided windshield, round roof edges with tight radii, and doors which closed flush with the outer wall determined the clear, modern lines of the body. The side windows, however, were made appreciably larger and were thus more elegant than the small windows of the O 317; the wheel arches no longer were flared. The clear-cut, angular face was matched by the design of the rear end. The Mercedes-Benz O 321 H, and later the
O 302, would adopt this from the O 322. The new regular-service bus offered an astonishing amount of space: in normal use there was room for 50 standees in addition to 32 seated passengers. At rush hour the O 322 even was allowed to carry 100 passengers. They entered and exited through a two-part inward folding door at the front and a four-part inward folding door before the rear axle. At the front entrance the passengers profited from a wide door cutout made possible by the steep, high windshield.
Fine little feature: the bus stop brake
The technical credentials of the O 322 also were quite impressive. Mercedes-Benz relied on innovative all-air suspension without additional leaf springs, introduced two years earlier to large-scale bus manufacture in the O 317. For the first time, the work of the driver was facilitated by a small detail on the O 322 which every urban bus has today: the bus stop brake, with a small lever on the instrument panel, conveniently held the bus in place during a short stop. In addition, drivers profited from the maneuverability of the bus and excellent visibility. The turning circle was just 18.4 meters. The new developments built into the O 322 included hydrostatic fan drive: the fan of the radiator was not always engaged, but cut in when coolant temperatures exceeded 84°C.
In 1960 the Mercedes-Benz O 322 was a state-of-the-art bus which in its details pointed ways to the future. Still, demand kept within limits: as an additional regular-service bus variant it was hedged in between the two success models, O 321 H and
O 317. The short career of the O 322 came to an end after just four years. Its successor was an urban bus edition of the famous O 302 series, whose career was launched in 1965. A few years later, in 1969, the history of urban regular-service buses was to take a completely different turn: series production of the highly specialized standard bus
O 305 then commenced. It opened a new page of bus history which would extend down to the ultramodern Mercedes-Benz Citaro urban regular-service bus of the year 2000.