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This paper describes the engine test and extended oil drain field performance of new synthetic engine oil technology developed for use in North American low-emission heavy-duty diesel engines. The resulting formulation utilizes an advanced additive system specifically tailored for synthetic base stocks which exceeds current industry and engine builder targets in critical performance tests. Use of synthetic base stocks allows the formulation of engine oils with a unique combination of performance characteristics, which include meeting SAE 5W-40 viscosity requirements for cold starting benefits while maintaining low volatility loss at high temperature for oil consumption control. In addition to meeting API CG-4, CF-4, CF-2, CF, SH and EC requirements, this technology has also demonstrated exceptional performance in extended-length diesel and gasoline engine tests. Furthermore, it has also performed very well in extended service interval field tests.

Since the early 1970's, the dominant trend in aircraft gas turbine engines has been increasing fuel efficiency. This has resulted in higher operating temperatures which, along with other engine design changes, place additional stress on the lubricant. This paper describes the laboratory evaluation of an oil developed to meet those more demanding conditions and presents field performance evidence in support of expectations based on laboratory tests.

A comprehensive study was conducted to evaluate additives for their ability to reduce the coefficient of friction of synthetic engine oils using a laboratory bench test apparatus. A class of additives was identified that also proved effective in providing fuel economy benefits when tested in vehicle dynamometer evaluations. Additional investigations using the proposed ASTM Five Car Energy Conserving Engine Oil Test Procedure confirmed the fuel saving performance of this specific additive class. This paper also discusses overall engine performance of synthetic engine oils formulated using this unique type of friction reducing additive. A full series of API SF/CC/CD quality level sequence tests, including critical extended length evaluations, was performed and excellent performance was demonstrated.

Single and multigrade engine oils formulated with catalytic hydrodewaxed (MLDW) base stocks possess low-temperature fluidity properties superior to counterpart products using conventional solvent dewaxed base stocks. This low-temperature benefit for MLDW oils is demonstrated in CCS and MRV viscosity measurements and cold engine cranking studies. This advantage is a natural consequence of the composition differences imposed by the respective dewaxing processes. The MLDW process is more selective and more efficient than solvent dewaxing in the removal of paraffins to reduce lube oil pour point. It follows that MLDW oils have fewer paraffins available for wax-gel formation at low temperatures. The lower paraffin content is also responsible for the lower VI values for the MLDW base stocks. Thus, the superior low-temperature performance of MLDW oils is contrary to viscosity-temperature extrapolations.

Methanol continues to be an important alternative fuel candidate for use in spark ignition engines. In addition to its potential as an alternative energy source, methanol has been claimed to provide benefits in possibly reducing reactive hydrocarbon emissions which contribute to ozone formation. This has resulted in considerable interest in using methanol fuels in several U.S. urban areas to assist in air pollution reduction. As a result of government incentives on these issues, engine builders are now developing new generations of vehicles capable of operating on methanol. Lubrication of these engines will require methanol-compatible oil formulations. Test work has shown that some current quality engine oils, designed for use with gasoline fuel, severely limit engine durability due to excessive wear of the valve train, cylinder bore, and bearings. A laboratory engine test program using a 2.3-liter engine has been conducted to evaluate methanol-fueled engine lubrication.

Automotive builders are designing future equipment for improved efficiency and greater durability. These designs will demand more performance and greater protection than ever before from the lubricants used. This paper reviews the performance available from a range of fully synthetic automotive lubricants, including engine oil, gear oil, automatic transmission fluid and grease. The development of optimized synthetic formulations to provide outstanding high temperature deposit and wear protection while maintaining excellent low temperature fluidity and pumpability, even after extended duration operation, will be discussed. The superior performance of synthetic lubricants compared to premium mineral oil lubricants will be demonstrated in a variety of laboratory equipment tests. Additionally, results will be presented from field testing under severe conditions and extended service periods in a variety of applications, including Formula 1 and Indianapolis race cars.