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In an automotive power train system, the differential gear system plays a vital role of enabling the vehicle to transfer the engine torque to the wheels. The differential system consists of complex system of gears which are meshed with each other. Effective lubrication of the differential system ensures that the metal to metal contact between the gears is avoided. In addition, the lubricants also acts as a thermal medium to effectively dissipate the heat produced due to frictional resistances. For dipped lubrication system, the use of lubrication oil leads to a loss of transmission power, and the loss increases with increasing rotational speeds. Prediction and an understanding of the transmission loss inside the differential system is important as it provides a means to increase the power transmission efficiency. In addition, it provides insights to optimize the lubrication methods, gear profile, and gear housings.

Engine Monitoring System (EMOS) plays a crucial role towards engine safety and monitoring for low cost commercial vehicles not equipped with a full-fledged Engine Management System (EMS). The EMOS system mainly focuses on monitoring of coolant temperature, alternator belt failure, and lubrication oil pressure and coolant level indication This paper describes various engineering design considerations for balancing the application requirements with implementation costs. It also highlights some common pit-falls in detecting alternator failures leading to nuisance trips as well as system design considerations involved in matching the gauge indication accuracy with the coolant high temperature trip point. The system designer needs to take into account, difference between alternator belt slippage versus total belt failure condition and implement different control strategies accordingly.

Common rail direct injection technologies have enabled the development of very high power and torque for a given capacity of the engine. These high performance engines have very high brake mean effective pressures and peak firing pressures. These high pressures increase the blow-by gas flow in cylinder crankcase. Vehicle brake assist systems as well as some actuators on engine need the vacuum. The vacuum is generated by the vacuum pump driven by the engine cam shaft or separately as accessory drive. The air pulled for creating the vacuum gets mixed with the lubricating oil. This air mixture with the lubrication oil gets circulated in the blow by circuit. Collectively, blow-by gases and the vacuum pump oil with air carry substantial engine oil particles. These oil particles need to be separated before connecting to the air intake circuit to reduce oil consumption and to reduce exhaust emissions. Generally cyclone type oil mist separation systems are used on the automobile engines.