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The direct injection common rail technology coupled with variable geometry turbocharger on the modern diesel engine has improved the diesel engine performance (power and torque) greatly as compared to the conventional diesel engine. Diesel engine performance is greatly dependent on the abundant air availability. And it is facilitated by Variable Geometry Turbocharger (VGT) in modern engines. The engines with variable geometry turbocharger offer quick response to the demand in various driving conditions especially in transient driving conditions. During transient driving conditions, the air intake system experiences a rapid air flow pressure and velocity changes. The pressure differentials across air intake system during transient events allow flow direction changes in the system. This kind of phenomenon generates unusual “Multiple Whoosh” noises in the air intake system of the sport utility vehicle engine.

NVH performance of powertrain [PT] is a critical parameter for vehicle NVH refinement. Ingress of PT-radiated noise to the cabin can be restricted by blocking the air born noise paths using combination of sealing, shielding and absorption. Isolation of vibrations to the body is achieved by soft rubber-mounting of PT at idling and low speeds. At higher speeds, when PT-support brackets, Frame, Body and other driveline components go into self-resonance, isolation provided by the rubber-mounts have limitations. Control of excitation at source itself will be a solution on this background [1]. In presence of strong transfer paths through driveline support, a direct correlation between flexural modes of PT and In-cab booms can be observed during vehicle operation [2]. Current work presents an overview and approach for refinement of PT including use of front-loading technique in the early design stage for modal refinement, testing and correlation.