Abstract: A friction testing positioning device (10) comprises a first wheel (12) rotatably mounted around a first axis (14) at a first end section of a transmission arm (16), said transmission arm (16) being pivotably mounted around a second axis (18), at least one second wheel (20) rotatably mounted around a third axis (22) at a second end of said transmission arm (16) and a transmission means (24) connecting said first axis (14) and said third axis (22), wherein said at least one second wheel (20) engages a substructure (26) and said first wheel (12) and said at least one second wheel (20) are being arranged to rotate at different speeds of rotation. A first vertically adjustable displacement means (28) operates on said transmission arm (16) to rotate around said second axis (18) and to press said first wheel (12) into engagement with said substructure at a substantially constant vertical force.