The "classic" 900 is based on the Saab 99 chassis, though with a longer front end to meet U.S. frontal crash regulations. The 900 was produced in 2- and 4-door sedan, and 3- and 5-door hatchback configurations; additionally, from 1986, a cabriolet (convertible) model was produced. There were single- and twin-carburetor, fuel-injection and turbocharged engines, including both Full Pressure Turbo (FPT), and in European models during the early 90s, Low Pressure Turbos (LPT).
The Saab 900 was a front-engined, front-wheel-drive compact car with a longitudinally-mounted, 45-degree slanted, inline 4-cylinder engine, double wishbone front suspension and beam-axle rear suspension. In its heyday, the 900 was popular with drivers who enjoyed its comfort, safety, practicality (especially hatchbacks), and highway driving manners.
Like its predecessor the 99, the 900 contained a number of unusual design features that distinguish it from most other cars. Firstly, the engine was installed 'backwards', with power delivered from the crank at the front of the car. Secondly, the transmission, technically a transaxle, bolted directly to the bottom of the engine to form the oil pan (albeit with separate oil lubrication). Power from the crank would thus be delivered out of the engine at the front, then transferred down and back to the transmission below, via a set of chain-driven primary gears. Similarly, Minis also had their gearbox mounted directly below the engine; however, the Mini gearbox and engine shared the same oil, whereas the Saab 900 (and 99) gearboxes contained a separate sump for engine oil.