Elastomer materials have gained considerable attention because they possess the potential to accomplish improved properties by the addition of even small quantities of nanofillers into elastomer matrix. Nanofillers play two important roles in rubber blends. The first is to improve the mechanical properties and the second one is to adjust the compatibility and morphology of the rubber blends. Filler-to-rubber interaction is important parameter in the reinforcement of rubber. In the presented study, (3-Aminopropyl)triethoxysilane (APTES) and 3-(Trimethoxysilyl)propyl methacrylate (TMSPMA) were used as a silane coupling agents in order to modify the bentonite filler.  Two different silane treatment methods were used to improve the reinforcing effect of bentonite in rubber blends. The first method was chemical silanization with silane coupling agents in ethanol solution.  The second method was also chemical silanization with silane coupling agents in ethanol solution but the pH was modified to make the silane coupling agent easier hydrolyze. The silanized bentonites were mixed into rubber blends as a partial replacement of carbon black. This work is focused on the study of the silane coupling agent effects on viscoelastic properties of bentonite-filled rubber blends. The quality of the filler-to-polymer as well as filler-to-filer interactions was evaluated owing to determining the viscoelastic properties  of the filled blends. The measurements were investigated via PRPA 2000 (production rubber process analyzer) tests, using the so-called Payne effect. This research work has been supported by the Operational Programme Integrated Infrastructure, co-financed by the European Regional Development Fund by the project: Advancement and support of R&D for "Centre for diagnostics and quality testing of materials" in the domains of the RIS3 SK specialization, Acronym: CEDITEK II., ITMS2014+ code 313011W442.