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Automobile customers are looking for higher performance and quieter comfortable rides. The driveline of a vehicle can be a substantial source of NVH issues. This paper provides an understanding of a driveline noise issue which can affect any variant of driveline architecture (FWD, AWD, RWD and 4X4). This metallic noise is mostly present during the take-off and appropriately termed as ting noise. This noise was not prevalent in the past. For higher fuel economy, OEMs started integrating several components for lighter subsystems. This in effect made the system more sensitive to the excitation. At present the issue is addressed by adding a ting washer in the interface of the wheel hub bearings and the halfshafts. This paper explains the physics behind the excitation and defines the parameters that influence the excitation. The halfshaft and the wheel hub are assembled with a specified hub nut torque.

Vehicle wind noise testing is usually done at elaborate tunnel facilities with minimal tunnel background noise, Techniques to reduce the tunnel noise, such as acoustic panels or improved fan systems, translate into higher costs for wind noise testing. We introduce an innovative procedure using an adaptive filtering algorithm to separate the tunnel noise from the wind noise inside the cabin of the vehicle. This new technique is capable of artificially reducing the tunnel background noise at low frequencies. Such a procedure has the potential to dramatically improve the wind noise testing capability of any wind tunnel, without the need for costly acoustic treatments.