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The automotive industry is one of the industries that have visibility suffered a strong demand for higher environmental performance. This industry have enjoyed years as the main source of employment and economic growth, today it is being pointed out as one of the major contributors to air pollution in urban centers. Indeed the benefits of automobile provide the means of gaining access to life's necessities and employment and a source of pleasure. However, despite these benefits there are environmental burdens as well: local air pollution, greenhouse gas emissions, road congestion, noise, mortality and morbidity from accidents and less open space to roads. Thus companies in the sector have been trying different strategies to overcome these challenges Evaluation of Emission development for commercial vehicles had always been great challenge to continuously migrate from one level of emission norm to other maintaining the business continuity.

The present work focusses on the Noise &Vibration refinement carried out on a Heavy commercial vehicle (HCV). In a heavy commercial 4×4 vehicle the existence of an auxiliary gearbox (AGB) is primarily for switching between the multiple drive options. The AGB can become an additional source of noise from the drive train. In this particular vehicle the overall noise from the vehicle has particularly been dominated by the noise from the AGB in specific drive options and conditions as experienced during the subjective assessment of the vehicle initially. First assessment was made by modifying the gear tooth geometry and then the gears were changed from spur to helical as a part of the AGB refinement process. The results of both these assessments were compared. A considerable improvement in the AGB noise was thereby achieved.

In the automotive industry several attributes needs to be considered for the development of a new vehicle which are important for the customer, such as vehicle dynamics, driveability, fuel consumption, emissions, durability and NVH among many others. Sometimes these characteristics are conflicting and often need is to create a robust trade-off where the design space is sufficient to fit all of them in a vehicle that rhymes with the brand image and is appealing to the intended customer. Automobile manufacturers try to meet the requirements with respect to quality and comfort and often, emotional, aspects supercede the previous objective, pragmatic demands. The satisfaction of the demands by the customers concerning comfort, driving pleasure, design appears dominant and functionality criteria sometimes takes a back seat. NVH is considered to be one of the key buy in factor among the above mentioned attributes.

This paper describes a methodology for design and development of On-Board Diagnostic system (OBD) with an objective to improve current reliability process in order to ensure design & quality of the new system as per requirement of commercial vehicle technology. OBD is a system that detects failures which adversely affect emissions and illuminates a MIL (Malfunction Indicator Lamp) to inform the driver of a fault which may lead to increase in emissions. OBD provides standard and unrestricted access for diagnosis and repair. Below given Figure 1 shows the working principle of OBD system. The exhaust emission of a vehicle will be controlled primarily by Engine Control Unit (ECU) and Exhaust Gas After Treatment Control (EGAS CU). These two control units determine the combined operating strategies of the engine and after treatment device. Figure 1 Modern Control Architecture for OBD System in Commercial vehicle [1]