The pipeline system that is composed of fiber reinforced rubber hoses is subject to various severe dynamic excitations once an air conditioning system is mounted on vehicle, and the prolonged exposure of air conditioner to the severe vibration environments may cause micro cracks and leakage of rubber hoses. Therefore, rubber hoses are desired to have high damping performance to suppress the excessive structural vibration. Meanwhile, the fixing bracket is usually manufactured with aluminum to reduce the total weight, but it is also desired to be replaced with other material for the sake of production cost down. In this context, the natural frequencies, frequency responses and the vibration acceleration levels (VALs) of the pipeline system are analyzed by the finite element analysis and the vibration experiment was performed. As well, the vibration damping characteristics of the five-layered reinforced rubber hoses of automotive air conditioner are parametrically investigated with respect to the rubber hose hardness and the material type of fixing bracket. It is found that the soft rubber hoses provide the best damping performance, which is also verified through the actual vibration experiment. In addition, the possibility of changing the bracket material to reduce the production cost is also confirmed.