Some of the newly constructed highway pavements in the Kingdom of Saudi Arabia have shown premature failures with consequential negative impacts on both roadway safety and economy. A major type of these failures is permanent deformation (rutting). Fillers were suspected to be major contributors to rutting susceptibility. The effect of filler type and content on the rutting potential of asphalt concrete as well as other mixes properties was investigated. The wheel tracking test (LCPC) was employed to investigate susceptibility of these mixes to rutting. The mechanical properties of mixes were studied using tests such as resilient modulus, indirect tensile strength, Hveem stability and Marshall criteria. Results of this study indicate that partial replacement of limestone dust by hydrated lime or portland cement aggravates resistance of the mixes to rutting. Furthermore, an analytical model was developed for predicting rutting potential based on various mixes properties.