,
Chile The B9S was launched in 2002 to replace the Volvo B7L, although production of the latter continued. It was intended to replicate the success of the Volvo B10MA and Volvo B12MA. The new chassis was conceived as a mid-engined articulated bus, with low floor at least in 40% of its length and an engine of less than 10 liters of displacement. Volvo had recently launched a new 9,4 liter engine used in the
FM truck series, appearing as alternative against models such as the Van-Hool AG300 and AGG300 that were using 12-liter engines. Placing a vertical engine in the centre of the frontmost section of the articulated bus avoided a wider useless space, freed up rear space, and allowed more even weight distribution. Unlike the prior B10MA/B12MA, the B9S has a step-free entrance and was fully wheelchair-accessible. Initially made in the Volvo Buses plant in Borås, Sweden, it was offered in two versions: • The B9SLEA, with low entry • The B9SALF, with an entirely low floor They were offered with a frontmost section wheelbase of 6.4 meters and bodied by Säffle, as a complete Volvo 7500 bus. Buses made up to 2005 used the Volvo D9A engine (340 bhp); then switched to the Volvo D9B engine (360 bhp) to confirm to the Euro 4 and Euro 5 emissions rules. In 2005, the platform's production was extended to Volvo Buses' factory in Curitiba, Brazil, which accommodated an order of 1,159 B9SALF units for the urban system of Santiago, Chile. The order required the modification of the frontmost section to 5 meters to avoid problems of maneuverability in narrow streets. Between 2007–2010, about 100 additional units were made there for Chile, and 100 for Brazil.