  We explore beyond Standard Model (bSM) physics signatures in the $l+jets$
channel of $t\overline{t}$ pair production process at the Tevatron and the LHC.
We study the effects of bSM physics scenarios on the top quark polarization and
on the kinematics of the decay leptons. To this end, we construct asymmetries
using the lepton energy and angular distributions. Further, we find their
correlations with the top polarization, net charge asymmetry and top forward
backward asymmetry. We show that used together, these observables can help
discriminate effectively between SM and different bSM scenarios which can lead
to varying degrees of top polarization at the Tevatron as well as the LHC. We
use two types of coloured mediator models to demonstrate the effectiveness of
proposed observables, an $s$-channel axigluon and a $u$-channel diquark.
