  The mathematical modeling and the stability analysis of multi-lane traffic in
the macroscopic scale is considered. We propose a new first order model derived
from microscopic dynamics with lane changing, leading to a coupled system of
hyperbolic balance laws. The macroscopic limit is derived without assuming ad
hoc space and time scalings. The analysis of the stability of the equilibria of
the model is discussed. The proposed numerical tests confirm the theoretical
findings between the macroscopic and microscopic modeling, and the results of
the stability analysis.
