Helical gears are used more commonly than spur gears due to their higher load carrying capacity, efficiency and lower noise. Helical gear pairs consist of base and axial planes in the plane of action. Transmission Error (TE) is considered as a dominant source of gear whine noise so gears pairs are analyzed and designed for lower TE. In process of designing helical gears for lower TE, the shuttling moment can be a significant excitation source. A shuttling moment is caused by the shifting of the centroid of the tooth normal force back and forth across the lead. Shuttling force is produced by a combination of design parameters, misalignment and manufacturing errors. Limited details are available on this excitation and its effect on overall noise radiated from the gear box or transmission at is gear mesh frequency and harmonics. LDP provides shuttling force as a bearing force in the base plane direction at one edge of the face width only. A more accurate method was developed by finding the centroid of the mesh forces at each rotation increment and calculating the moment based on the motion of that centroid over one tooth mesh increment. In this paper, a detailed methodology is developed to predict the dynamic response of helical gear pair with a shuttling moment using LDP and Finite Element Analysis (FEA). Three helical gears are identified from literature. Gear pairs are selected in so that they are designed for low TE at design torque. TE and the shuttling moment are predicted by using LDP for the selected gear pairs and it is verified through published literature. Gear pair assemblies are modeled in ANSYS and analyzed for response due to TE force and shuttling moment. FEA results show that TE and the shuttling force can excite different modes.. A methodology is established for understanding the contribution of TE and the shuttling force in the radiation of noise from the gearbox structure. This methodology helps in identifying the dominant source out of the TE and shuttling moment before performing dynamic analysis and design gears for lower excitations. This can also capture the exact behavior and increases the accuracy of the model. An attempt has been made to design gears for lower TE and shuttling moments with the help of gear micro geometry without affecting the other parameters, such as efficiency and stress.