In this paper, we consider a vehicle routing problem with pickup & delivery and synchronization constraint. One vehicle with a known and finite capacity has to visit n customers to pickup or deliver empty containers. At the same time, another vehicle has to deliver ready-mixed concrete by pouring it into the previously delivered containers. This implies dealing with capacity and temporal precedence constraints. We propose a heuristic to tackle this problem. A two-step approach including a local search and a constructive algorithm. We provide some experiments that show positive results.