To expend the field of application of LC indicators of shear stresses and to modify the LCs rheological properties, special additives may be used. In the paper the effect of selective reflection of cholesteric liquid crystals planar texture is considered under conditions of mechanical shear by subsonic flow. Comparison of shear sensitivity of LC mixtures with silica particles and without one is presented. It was stated the SiO2 additives (1% w.) results in the lesser sensitivity of selective reflection to shear due to increased viscosity.