In this paper, we consider a company including both a forward supply chain producing and supplying products to markets and an after-sales supply chain providing spare parts to fulfill after-sales commitments. Uncertainties in estimating product demand in the pre-markets, spare parts demands in the after-sales markets and qualified outputs of production facilities throughout these two chains are considered in this problem. Stochastic qualified output of production facilities are due to their imperfect productions systems. We show that uncertainties propagate and qualified flow depreciates by moving material, components and products from the upstream to the downstream of these supply chains and these phenomena should be quantified to determine the service levels of this company in the pre and after-sales markets. Reliable flows preserve chains' service levels against uncertainties and their propagated effects. The consideration of the interactions of preand after-sales operations as concurrent planning of these two chains and considering both demand and supply side uncertainties and their propagated effects are the important contributions of this paper. Here, we propose a mathematical model for determining the best marketing strategies for this company (price, warranty length and service levels) and preserving reliable flow dynamics throughout the chains' networks. The proposed model and its solution approach are tested using data from an engine production company. We derive some managerial insight by analyzing the correlations among the marketing strategies and how they affect each other.