A set of lane changing rules for cellular automata simulating multi-la
ne traffic is proposed, It reproduces qualitatively that the passing l
ane becomes more crowded than the one for slower cars if the flux is h
igh enough, which is true for motorways in countries like Germany wher
e passing should be done on a specified lane as a rule. The rules have
two parameters allowing to adjust the inversion point of the lane-usa
ge distribution and to calibrate the model.