In 1956, the contractor Osterreichische Saurer-Werke
(which was taken over by Steyr-Daimler-Puch AG in 1970) started development of an armoured personnel carrier. The first prototype, the 3K 3H, was completed in 1958 and the second, the 4K 3H, the following year. They are both powered by a Saurer 3H 200 hp diesel engine.
The next model, the 4K 2P, had a different hull layout, a new torsion bar suspension and was powered by a 250 hp Saurer 2P diesel engine. In appearance it was similar to the first production vehicles which were completed in 1961 and designated 4K 4F. Later production vehicles were the 4K 3FA (230 hp) and the 4K 4FA (250 hp), which differed only in minor details such as their Sauer engines.
A total of 445 production vehicles was delivered to the Austrian Army in the following versions: 30 4K 4F, 211 4K 3FA, 38 4K 3FA-FS, 12 4K 4FA-Fü/FIA, 15 4K 4FA-San, 76 4K 4FA-G2, 60 4K 4FA FüA 1 to 4 series, three 4K 3FA Fül and a number of 4K 3FA GrW1 81 mm mortar carriers which were conversions of earlier vehicles. Production was finally completed in 1969. The vehicle was succeeded in production by a new model, described in detail in a separate entry, called the 4K 7FA which uses the same automotive components as the SK-105 Kürassier
light tank also manufactured by Steyr-Daimler-Puch. Production of the 4K FA and SK 105 are complete and all marketing of these has ceased.
In mid-1999, the Austrian MoD awarded Steyr-Daimler-Puch a contract for the supply of 112 ASCOD
Ulan infantry fighting vehicles for the Austrian Army. These were delivered from 2002 to 2004 and has now replaced at least part of the current Saurer 4K 4FA APC fleet of the Austrian Army. The 4K 4FA series will remain in service with Austria for some time