  In this work we discuss a general approach for the dissipative dark matter
considering a nonextensive bulk viscosity and taking into account the role of
generalized Friedmann equations. This generalized $\Lambda$CDM model
encompasses a flat universe with a dissipative nonextensive viscous dark matter
component, following the Eckart theory of bulk viscosity. In order to compare
models and constrain cosmological parameters, we perform Bayesian analysis
using one of the most recent observations of Type Ia Supernova, baryon acoustic
oscillations, and cosmic microwave background data.
