Sisu KB-45 is a light off-road lorry made by the Finnish heavy vehicle producer Suomen Autoteollisuus (SAT) in 1965–1970.

The two-axle, all-wheel-drive vehicle[2] with payload of 4,000 kg[3] was developed after an assignment of the Finnish Defence Forces.

The decision was based on the Defence Forces' measuring results of average distances between trees in the Finnish forests.

A long drive shaft between them had to be substituted by a structurally challenging gear socket system which enabled a shorter distance.

At the same time the production was moved from Karis to Hämeenlinna, the former Vanaja factory which was merged with SAT in beginning of 1969.

The suspension consists of longitudinally mounted leaf springs and two-way acting telescopic shock absorbers.

[3] The good off-road capability is carried out by a torsionally bending frame structure and middle located engine which enable an even wheel load even in rough terrain.

During the validation tests, the vehicle was driven up 60% steep hills and it could also withstand a 45% side slope without falling.