We consider a type of quantum electromechanical system, known as the shuttle system, first proposed by Gorelik et al. Phys. Rev. Lett. 80 4526 (1998) We use a quantum master equation treatment and compare the semiclassical solution to a full quantum simulation to reveal the dynamics, followed by a discussion of the current noise of the system. The transition between tunneling and shuttling regime can be measured directly in the spectrum of the noise.