In order to reduce raw material costs, thermoplastic elastomer (TPE) resins were produced using recycled materials. In particular, post-consumer polyethylene and ethylene-propylene diene monomer (EPDM) were used as the main matrix. Nevertheless, a coupling agent based on maleated polyethylene (MAPE) was used to determine if interfacial properties can be modified. The compounds were processed via twin-screw extrusion and then pelletized. To detect any processing effect, compression and injection molding were used to produce the final parts. In this case, EPDM (0, 40, 50, 60, 80, 90%) and MAPE (0, 5, 10 phr) contents were modified to produce TPE with a wide range of properties. Based on the samples produced, a complete mechanical characterization in terms of tensile, torsion, and flexural properties was performed. The samples density and hardness were also studied. The results show that significant differences were obtained between compression and injection molding, while the effect of coupling agent addition is important with a transition EPDM content around 60% where a balance between rigidity, elasticity and strength can be obtained.