The present customer requirements in a commercial vehicle are fuel economy, cost, service and most importantly NVH. This requirement is strengthened due to high competition in CV business and with the inflow of more foreign players in the domestic market. Now NVH performance is one of the basic deliverables to the customer. Though noise ingress into cabin reduced by robust leak-proof cabins and bus body structures, certain noise sources remain hidden till the late design stages. They are identified only after all the elements are tested together in a wide variety of conditions. Driveline is one of those sources of noise and vibration which are identified upon vehicle level testing. Driveline excites the other vehicle structures across a wide band of frequencies in commercial vehicles which has impact on numerous NVH phenomena. Current work focuses on the driveline noise source identification and its reduction in a commercial vehicle. An abnormal noise is perceived in a in high gears at high speeds. This annoying noise is subjectively perceived in geared and neutral coast down conditions. Objective NVH assessment including near source noise and vibration of the driveline components was performed to quantify the noise. Initial test results revealed that the driveline excitations are aggravated in auxiliary gear box as broadband rattle noise. The design configuration of the driveline components and related subsystems such as propeller shafts and gearbox etc. was studied to the find root cause of the excitations. The driveline configuration including the auxiliary gearbox tooth geometry and propeller shaft balancing were scrutinized and modified. These improvements proved betterment in noise and vibration results.