  A new flipped $SU(3)_C\otimes SU(4)_L\otimes U(1)_X$ model without exotic
electric charges is proposed. All the quarks families are arranged in the same
representation while leptons generations are in different representations
leading to a tree level FCNC. Moreover, It is shown that the cancellation of
the triangle chiral anomalies requires new additional leptons 10-plet and
quadruplet. All fermions masses have been also discussed. Furthermore, using
the most recent experimental data of the branching ratios of $\mu \to
ee\bar{e}$ and $\mu \to e\gamma$ rare decay modes, stringent bounds on the
heavy neutral bosons masses and the muon-electron mixing matrix element are
obtained.
