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Vehicle target setting is an evolving process based on continually changing internal (management, standards) and external (competitive and legal) requirements. In addition to evolving requirements, the process for establishing and documenting targets may not be clear. The objective of this paper is to detail the overall process of target setting, the critical factors to consider, and key definitions for each stage of the process. It will describe the complete process from early competitive benchmarking to final verification testing. Setting targets for a vehicle requires definition and thorough benchmarking of the competition, an understanding of the key attributes used to describe the vehicles' performance, and a clearly defined set of requirements. These requirements will be regulatory, corporate and competitively based and grouped by clearly defined, customer perceived attributes which can be cascaded to specific vehicle systems.

Improvement of engine fuel efficiency through the use of low friction engine oils is a major task in engine lubrication research. This friction reduction can be achieved by improving the rheological characteristics and elastohydrodynamic (EHD) properties of engine oils, and by controlling boundary chemical interactions between oil-based additives and lubricated components in the engine. In order to achieve minimal frictional power loss under all lubrication regimes, engine tribological systems must be designed to effectively use advanced lubricant technology, material and surface modifications. This paper presents results of cooperative research addressing opportunities for minimizing friction through extension of hydrodynamic lubrication regime in lubricated components using various formulation approaches. A set of experimental oils has been evaluated using laboratory test rigs that simulate hydrodynamic, EHD, mixed and boundary lubrication.

This paper is the first in a series of documents designed to record the progress of the SAE J2293 Task Force as it continues to develop and refine the communication requirements between Plug-In Electric Vehicles (PEV) and the Electric Utility Grid. In February, 2008 the SAE Task Force was formed and it started by reviewing the existing SAE J2293 standard, which was originally developed by the Electric Vehicle (EV) Charging Controls Task Force in the 1990s. This legacy standard identified the communication requirements between the Electric Vehicle (EV) and the EV Supply Equipment (EVSE), including off-board charging systems necessary to transfer DC energy to the vehicle. It was apparent at the first Task Force meeting that the communications requirements between the PEV and utility grid being proposed by industry stakeholders were vastly different in the type of communications and messaging documented in the original standard.

This paper is the second in the series of documents designed to record the progress of a series of SAE documents - SAE J2836™, J2847, J2931, & J2953 - within the Plug-In Electric Vehicle (PEV) Communication Task Force. This follows the initial paper number 2010-01-0837, and continues with the test and modeling of the various PLC types for utility programs described in J2836/1™ & J2847/1. This also extends the communication to an off-board charger, described in J2836/2™ & J2847/2 and includes reverse energy flow described in J2836/3™ and J2847/3. The initial versions of J2836/1™ and J2847/1 were published early 2010. J2847/1 has now been re-opened to include updates from comments from the National Institute of Standards Technology (NIST) Smart Grid Interoperability Panel (SGIP), Smart Grid Architectural Committee (SGAC) and Cyber Security Working Group committee (SCWG).

Rheological measurements were performed on a series of lubricants for flexible fuel vehicles, and blends of water or methanol in these oils. A series of measurements, including kinematic viscosity, viscosity at low and high shear rates, low shear viscosity under borderline pumping conditions, and density were performed on all oils and blends. The effects of mixing conditions, such as mixing speed and temperature on these properties were also studied. Viscosity increases when water emulsifies in oils. Methanol exhibits limited solubility in all oils, but more so in synthetic base oils. Viscosity tests at 248 K (-25°C) do not indicate the onset of critical pumping conditions, even at high concentrations of water or methanol. Tests at high shear rates at 323 K (50°C) suggest that water-oil emulsions are quite stable, while methanol-oil blends lose their methanol content either due to evaporation or shear-induced separation.

A laboratory wear test is used to evaluate the wear protection properties of new and used engine oils formulated for FFV service. Laboratory-blended mixtures of these oils with methanol and water have also been tested. The test consists of a steel ball rotating against three polished cast iron discs. Oil samples are obtained at periodic intervals from a fleet of 3.0L Taurus vehicles operating under controlled go-stop conditions. To account for the effects of fuel dilution, some oils are tested before and after a stripping procedure to eliminate gasoline, methanol and other volatile components. In addition to TAN and TBN measurements, a capillary electrophoresis technique is used to evaluate the formate content in the oils. The results suggest that wear properties of used FFV lubricants change significantly with their degree of usage.

A short engine sequence test, based on the Sequence VD procedure, was used to screen FFV oil candidates more rapidly. Since only one engine is needed to compare the wear-protection performance of several lubricants, engine hardware variability is not a significant issue in this test procedure. Several lubricants, some specially formulated for FFV engines, were tested using standard Sequence VD engine hardware which includes molybdenum top piston-rings. Results showed clear discrimination of the performance of oil candidates. These lubricants were also tested using an engine with chromium-faced top rings and exhibited similar performance ranking.

The variation of viscosity with temperature and shear rate plays an important role in the analysis of lubrication of automotive systems. In this paper, a method for predicting the viscosity of non-Newtonian fluids, such as multigrade engine oils, over a wide range of temperatures and shear rates is outlined. This expression determines viscosity parameters for shear thinning fluids in terms of easily measured viscosity values at some reference state. A comparison of predictions with experimental data suggests that viscosity for multigrade engine oils can be predicted to within experimental uncertainty. The proposed method can be used in assessing lubricant viscosity at shear rates greater than 106 s-1, which are beyond the capability of current laboratory instruments. A comparative study with multigrade oils shows that performance at very high shear rates cannot be accurately gauged from high temperature, high shear (HTHS) viscosity measurements.

A 1.8L turbocharged diesel engine valvetrain friction was investigated, and the effectiveness of using a solid film lubricant (SFL) coating in reducing friction was determined throughout the operable speed range. This valvetrain design features direct acting mechanical bucket valve lifters. Camshaft journal bearing surfaces and all camshaft rubbing surfaces except lobe tips were coated. The direct acting bucket shims were etched with a cross hatch pattern to a depth sufficient to sustain a SFL film coating on the shim rubbing surfaces subjected to high surface loads. The SFL coated valvetrain torque was evaluated and compared with uncoated baseline torque. Coating the cam bearing journal surfaces alone with II-25D SFL reduced valvetrain friction losses 8 to 17% for 250 to 2000 rpm cam speed range (i.e. 500 - 4000 rpm engine speed). When bucket tappet and shims were also coated with the SFL, further significant reductions in coated valvetrain friction were observed.

A measure of functional degradation or its surrogate is more informative than attribute data such as failure time when improving designs or developing meaningful tests. This paper delineates the advantages and disadvantages of using degradation data, and the situations under which one should or should not use degradation analysis. A comparison has been done between degradation testing, testing to failure, and bogey testing. The steps necessary to apply degradation analysis techniques to product design have been described: determine scope of the project, plan degradation test, collect data, analyze data, and document results. A case study has been used to demonstrate the whole process of degradation analysis techniques.

The development, evaluation, and selection of Plasma spray powder material for the coating of aluminum-alloy engine cylinder block bores was conducted to yield a bore system which provides numerous benefits relative to the present cast iron sleeve system. These include: a reduction in ring/bore wear, friction, and in engine oil consumption as well as a benefit in reduced corrosion. A reduction in engine weight, overall costs, and improvements in machining and honing operations are shown. Alternate thermal spray processes are also described in this investigation. Test evaluation leads to the selection of two plasma powder material spray systems. One system emphasizes low cost relative to the present system. The second system provides significant reduction in friction and ring/bore wear through the introduction of solid lubricant in the material composition.

Application process, and performance in engine dynamometer and high mileage vehicle fleet durability tests of Plasmaspray coated bore aluminum block engines are discussed. Fuel economy, oil consumption, power and wear data for Ford 4.6L-V8 aluminum block engines utilizing very low cost iron/iron oxide base coatings, and stainless steel/BN solid film lubricant Plasmasprayed coatings are presented. Test results from Ford's 100 hour Piston & Gasket Engine Dynamometer Durability Tests, and Fleet Vehicle Durability Tests show ring/bore wear reductions of more than 40% relative to production cast iron bore systems with Oil Economy averaging more than 13,600 km/l (8000 mi/qt).

An investigation describing engine friction reduction benefits attainable via the introduction of Solid Film Lubricants to piston skirts is presented. Ford II-25 thermoset and II-25 waterborne molybdenum disulfide based solid film lubricants were shown through single cylinder motored engine experiments, to produce piston system friction reductions of 12 to 17% at 1500 rpm. Further tests undertaken in fired engine dynamometer studies, on a 1.91 1-4 CVH engine, demonstrated total engine friction reductions of 6% at W.O.T. conditions. The reduced engine friction resulted in lowering BSFC at 850 rpm by 3 to 4%. Tests conducted by Powertrain Operations confirmed durability. II-25 thermoset was selected for production implementation on all new Ford engines starting from model year 1995.

Fuel efficient engine oils containing molybdenum dialkyldithiocarbamate, MoDTC, friction modifiers can lose their ability to reduce friction during service prematurely. Depletion processes involving antioxidant reactions and interactions with other additives play important roles in determining the performance of these formulations. This paper describes results from investigations of the antioxidant reactions of MoDTC alone and in combinations with zinc dialkyldithiophosphates and a phenolic antioxidant. The effect of supplementary ashless antioxidant on retention of friction reducing capability is described.

A laboratory axle efficiency test using a torque sweep method has been developed. Vehicle test limitations, previous axle efficiency tests and origin of current test are discussed. Test development, equipment and importance of technique are presented. Correlation with vehicle tests is shown and usefulness of data for evaluating lubricant and axle design changes is discussed. An evaluation of test results shows that the torque sweep method has the capability of identifying changes that may not show with vehicle tests.

THE study of engine life, carried out by investigating engine wear in typical service, and by then striving to find the most effective ways of controlling it, forms the basis of this paper on contaminants in lubricants. The investigation involved a study of engine wear in 20,000 miles of operation typical of the average driver. The average driver was selected by using test cars from an employee transportation car pool. At the conclusion of the tests it was found that the use of the full-flow oil filter proved to be the best method for restricting engine wear caused by contaminants that get inside the engine. It was also shown that after successfully eliminating large, solid particles, further restriction of engine wear would depend upon the ability of the oil to lubricate, and upon the engine design to provide the oil supply in a manner suitable for lubrication of each part of the engine.

In 1958 the Coordinating Research Council conducted an extensive series of vapor lock road tests at a centralized location to study the effect of test variables on the hot fuel handling characteristics of passenger cars. Two years later, another test program was carried out at a common location to determine the hot fuel handling characteristics of a selected group of 1960 cars, employing the vapor lock survey technique developed in the 1958 program. The results obtained from the two programs indicate that this technique provides a satisfactory basis for defining the more severe vapor handling characteristics of automobiles in a relatively short time.

This paper presents three test methods used to evaluate rear axle lubricants: the Ford motored rear axle test, the high speed Timken test, and the rear axle score test. In each instance, results are described, including the development of new rear axle test methods. Lubricants successfully completing these tests are considered for further evaluation.

Axle dynamometer tests were carried out to evaluate the effects of rear axle lubricant viscosity-temperature behavior and frictional characteristics on vehicle fuel economy. Using a Ford 9 inch 2.75:1.0 ratio axle, a set of input speed and load conditions was selected to permit simulation of the CVS and EPA highway driving cycles. Lubricant temperature was varied from -30°C to 100°C to simulate seasonal climatic effects. Data obtained for three lubricants differing in viscosity-temperature behavior were interpreted assuming a lubrication model including both elastohydrodynamic and mixed lubrication conditions. From these data, fuel economy projections were made using a vehicle simulation computer program. The results predict that improvements in vehicle fuel economy on the order of a few percent can be made at low temperatures by use of low viscosity synthetic lubricants, but only small effects are projected for the CVS and EPA highway cycles.