This study reports a reclamation method of ground tire rubber (GTR) and electronic wastes into a tunable stiffness composite namely magnetorheological elastomers (MREs). The composite matrix was the GTR that has been separated from its metals and yarns. Meanwhile, the fillers were fabricated from magnetic cores of the cathode ray tubes (CRTs) monitor waste through high energy ball milling in wet condition. Some physicochemical characterizations of the powders were initially conducted to collect the physical and chemical properties. Based on the examination, the ground powders were identified as pure magnetite (Fe3O4) having low remnant and high magnetization. The MREs samples were prepared by high-temperature high-pressure sintering. The mixed of crumb rubber and magnetite powder was vulcanized under simultaneous pressure, and temperature in the absence of magnetic fields resulted in an isotropic MREs type. The specimens were examined their abilities in responding to the external magnetic field through static and dynamic compression test. The experimental investigation showed that the static and dynamic stresses of the stiffness increased by the increment of magnetic fields until a particular point of flux density. The tunability of the stiffness indicated that the elastomers can provide wide ranges of the storage and loss modulus.