A noise attenuation device for a vehicle exhaust system is provided. The device includes an exhaust pipe having a passageway for receiving exhaust gas pulses from an engine. The device further includes a plurality of vanes extending from an inner surface of the passageway and spaced apart from one another and disposed upstream of a discontinuity in the exhaust pipe. The vanes reduce turbulence in the exhaust gas pulses flowing past the vanes to reduce noise at the exhaust pipe discontinuity.