Predicting the fleet requirement based on fleet productivity estimation is one of the critical parts of a robust long-term mine plan. The dispatch logic that determines the return destination of the empty trucks is significantly important in the overall full and empty travel distances and trucks’ productivity. In this paper, a Monte-Carlo simulation model is presented to mimic the real truck-and-shovel operations and measure trucks’ productivity in terms of Tonne Per Gross Operating Hour (TPGOH). A linear programming model is integrated into the simulation model to optimize the dispatch decision through distance minimization subject to the mine's production schedule. The historical data records of oil sands mining operations are used to validate model's performance. The results show significant improvement over the existing mine site's method with closely matching the real TPGOH and better estimation of the total empty travel distance, as a result of new dispatch model implementation.