Bus manufacturing, a sector of the automotive industry, manufactures buses and coaches.
Bus manufacturing had its earliest origins in carriage building. Other bus manufacturers had their origins in truck manufacturing. Historically, chassis designs were shared between trucks and buses, but in later years specific bus chassis have been developed, and the midibus introduced a lighter weight bus chassis than normal trucks.
Bus manufacture historically developed as chassis and body builds. Often, large bus operators or authorities would maintain separate stocks of bus bodies, and would routinely refurbish buses in a central works, and refurbished chassis might receive a different body. One of the first integral type bus designs combining the body and chassis was the AEC Routemaster.
In the 1980s, many minibuses were built by applying bus bodies to van chassis, so called 'van derived' buses. Many of these have been replaced by purpose built designs, although for smaller minibuses this is still an option.
In several parts of the world, the bus is still a basic chassis, front-engined bonneted vehicle; however, where manufacturers have sought to maximise the seating capacity within legal size constraints, the trend is towards rear- and mid-engined designs.
In the 1990s, bus manufacture underwent major change with the push toward low-floor designs, for improved accessibility. Some smaller designs achieved this by moving the door behind the front wheels. On most larger buses, it was achieved with various independent front suspension arrangements, and kneeling technology, to allow an unobstructed path into the door and between the front wheel arches. Accordingly, these 'extreme front entrance' designs cannot feature a front-mounted-engined or mid-engined layout, and all use a rear-engined arrangement. Some designs also incorporate extendable ramps for wheelchair access.
Further accessibility is being achieved for high-floor coaches, whereby new designs are featuring built-in wheelchair lifts.
While the overwhelming majority of bus designs have been geared to internal combustion engine propulsion, accommodation has also been made for a variety of alternative drivelines and fuels, as in electric, fuel cell and hybrid bus technologies. Some bus designs have also incorporated guidance technology.