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The effects of lubricating oil on friction and wear were investigated using light-duty 2.2L compression ignition direct injection (CIDI) engine components for bench testing. A matrix of test oils varying in viscosity, friction modifier level and chemistry, and base stock chemistry (mineral and synthetic) was investigated. Among all engine oils used for bench tests, the engine oil containing MoDTC friction modifier showed the lowest friction compared with the engine oils with organic friction modifier or the other engine oils without any friction modifier. Mineral-based engine oils of the same viscosity grade and oil formulation had slightly lower friction than synthetic-based engine oils.

Engine design and tribology engineers are constantly challenged to develop advanced products with reduced weight, reduced friction, longer life, and higher engine operating temperatures. The resulting engine systems must also meet more demanding emissions and fuel economy targets. Advanced energy-conserving lubricants and surface coatings are concurrently evolving to meet the needs of new engine materials. Because of the enormous cost and time associated with engine testing, much interest is being focused on the development of representative and repeatable bench tests for evaluation of engine materials and lubricants. The authors have developed a bench test employing reciprocating motion for evaluating friction and energy-conserving characteristics of lubricants.

The impacts of cylinder bore surface finish and coating treatment on the tribological characteristics of engine components were determined by using a modified Cameron-Plint Friction and Wear Tester. The friction and wear behavior of several honed cylinder bores was compared using plateau-honed and brush-honed bores in a normal, lubricated sliding wear mode. Several experimental thermal sprayed aluminum bores, prepared following a water jet cleaning process, were compared to production cast iron plateau-honed bores. For the cast iron bores, it was observed that most of the wear occurred within the first 2 hours of the run-in stage. In general, the combination of a cast iron bore sliding against molybdenum sprayed piston rings showed lower friction and wear compared to the thermal spayed aluminum bore samples sliding against the same rings. The rough-honed bore samples demonstrated much higher wear than the plateau-honed or brush-honed bores.

This new book provides a comprehensive overview of various lubrication aspects of a typical powertrain system including the engine, transmission, driveline, chassis, and other components. The manual addresses major issues and current development status of automotive lubricant test methods. Topics also cover advanced lubrication and tribochemistry of the powertrain system, such as diesel fuel lubrication, specialized automotive lubricant testing development, filtration testing of automotive lubricants, lubrication of constant velocity joints, and biodegradable automotive lubricants.