  We reanalyse the potential of the LHC to discover new $Z'$ gauge bosons and
to discriminate between various theoretical models. Using a fast LHC detector
simulation, we have investigated how well the characteristics of $Z'$ bosons
from different models can be measured. For this analysis we have combined the
information coming from the cross section measurement, which provides also the
$Z'$ mass and total width, the forward-backward charge asymmetries on- and
off-peak, and the $Z'$ rapidity distribution, which is sensitive to its $u
\bar{u}$ and $d \bar{d}$ couplings. We confirm that new $Z'$ bosons can be
observed in the process $pp \to Z' \to l^+ l^-$, up to masses of about 5 TeV
for an integrated luminosity of 100 fb$^{-1}$. The off- and on-resonance peak
forward-backward charge asymmetries $A_{\rm FB}^{l}$ show that interesting
statistical accuracies can be obtained up to $Z'$ masses of the order of 2 TeV.
We then show how the different experimental observables allow for a diagnosis
of the $Z'$ boson and the distinction between the various considered models.
