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Prior work by various OEMs has identified the ability of phosphorus-containing compounds to interfere with the efficiency of modern emissions control systems utilized by gasoline-powered vehicles. Considering the growing societal concerns about ecological effects of exhaust emissions, greenhouse gas emissions and related global climatic changes, it becomes desirable to examine the effect of reduced phosphorous (P) deposits in various vehicle makes, models and types of service, over the lifetime of a vehicle's operation. This paper assesses advantages and disadvantages of various methods to examine the path of P transfer throughout exhaust catalytic systems. Test types discussed include examples of bench testing focusing on catalyst compatibility, dyno mileage accumulation and field trial examinations.

Using a seven-step quality improvement process, some of the engine build-up factors adversely influencing the severity and precision of the Sequence VI dynamometer test were examined. Insights from engineering (theory) and database (statistical) analyses enabled a 23 factorial experiment to identify oil ring tension, piston ring side clearance, and piston fit as critical parameters in a 3-oil, 9-engine, 28-test program. High ring tension was shown to emphasize the friction reducing capability of higher performing oils and the deficiency of a lower performing oil. Interactions were noted. A helpful correlation of test severity with the engine calibration indicators was shown.

There is concern over water-in-oil emulsion formation in passenger cars in the field. Crankcase pressure measurements in the ASTM Sequence IID rust test have been used to indicate possible emulsion formation tendencies of lubricants. This paper presents the development of a short duration emulsion fleet test procedure which demonstrates low car-to- car variability and correlates well with a previous fourmonth winter emulsion fleet test. Physical emulsion characteristics and used oil analyses are described. Evaluation of both Sequence IID reference oils and commercial oils in this field test reveals a lack of correlation between Sequence IID crankcase pressure results and field performance. The new procedure has been applied to investigate the impact of additive and base oil variations on the emulsion-forming tendencies of lubricants in the field. Base oil variables such as viscosity grade, composition, and volatility were evaluated.

Motorcycle manufacturers have recognized that highly friction modified passenger car oils can be deleterious to clutch performance, leading to clutch slippage. To address this issue, a JASO specification for four-stroke motorcycle oils was developed in 1999, categorizing oils into high friction oils termed JASO MA and low friction oils termed JASO MB. The high friction oils were preferred for most motorcycles where the engine oil also lubricates the clutch and gears. New motorcycle transmission technologies have increased the number of dry clutch applications which has led to an increased demand for JASO MB oils to improve fuel efficiency. While JASO MB oils contain friction modifiers to improve initial fuel economy, the motorcycle specifications have not addressed the fuel economy durability of motorcycle oils.

Specific frictional properties are essential to provide correct and pleasurable shifting in a manual transmission. Synchroniser rings are being manufactured from an increasingly wider range of materials, and so it is important to understand synchroniser-additive interactions in order to develop tailored lubricants that provide the desired frictional performance. This paper describes a study of the interaction of various friction modifier additives with a range of synchroniser materials in order to better understand the potential to develop lubricants that provide optimal frictional performance across a wide range of manual transmission-synchroniser systems. This presentation will outline the results of testing fluids with a range of synchroniser materials and will be followed by a future paper that will describe details of the fluids and analysis of their interactions with the different synchroniser surfaces.

Our basic understanding of the chemical and physical nature of soot, its interaction with lubricant components and its role in promoting wear and oil thickening in heavy duty diesel engines continues to grow. Our current study in the GM 6.5L engine focuses on examining the effects of variations in base stock type (Group I vs. Group II), viscosity index improver or viscosity modifier (VM) chemistry (OCP vs. dispersant OCP), zinc dithiophosphate (ZDP) type and dispersant type (low MW vs. high MW) on roller follower wear, viscosity growth and other measured responses. In this study, more robust fluids were tested producing very low wear results and minimal viscosity increase of the lubricant. Fluids containing dispersant OCP (DOCP) and high MW dispersant produced a lower degree of wear, whereas varying the ZDP type (1° vs. 2°) showed no effect on wear. The use of Group II base stocks was associated with significantly lower viscosity increases.

A major drive to develop methanol-fueled vehicles began with the 1973 oil embargo. Early work with dedicated methanol-fueled vehicles demonstrated that lubricant choice influenced engine durability. The qualities desired were not defined by the gasoline engine oil classification system in place at the time. As a result oils were developed which optimized those properties deemed desirable for methanol fuel. The advent of fuel sensors made it possible to design a vehicle which can operate on gasoline or gasoline with varying levels of methanol without intervention by the operator. This created a need for a lubricant that can handle a diversity of methanol/gasoline mixtures as well as conventional gasoline. The paper reviews some of the lubricants that have been used in prototype methanol-capable vehicles and the improvement of these formulations to meet the latest gasoline engine performance criteria while maintaining satisfactory methanol performance.

Interactions between automatic transmission fluid (ATF) components and composite friction materials and their effect on friction system performance continues to be an active area of interest to the automotive industry. A more fundamental understanding is needed of how base fluids, ATF additives, friction materials, and transmission design interact to produce the observed transmission system performance and durability. We herein report results from investigations carried out using a relatively thermo-oxidatively stable polyalphaolefin (PAO) base fluid treated with components representative of several additive types we previously reported to have significant negative effects on frictional performance. Secondly, we investigated a conventionally refined 150 N base oil treated with a calcium sulfonate detergent previously shown to improve friction performance.

Water-emulsified diesel fuel technology has been proven to reduce nitrogen oxides (NOx) and particulate matter (PM) simultaneously at relatively low cost compared to other pollution-reducing strategies. While the mechanisms which result in these reductions have been postulated, the development of new analytical tools to measure in-cylinder soot formation using optically accessible engines can lead to a deeper understanding of combustion and the chemical and physical mechanisms when water is present during combustion. In this study, an optically accessible single cylinder engine was used to study how water brought into the combustion chamber via an emulsified fuel changes the combustion process and thereby reduces emissions. In-cylinder measurements of relative soot concentrations were used to determine the effect of water-emulsified fuel on soot formation.

The goal of this work was to find combinations of detergent and friction modifier additives that would produce high metal/metal friction with good clutch material performance. A baseline formulation was used with various combinations of five different detergents with five different friction modifiers. Two bench tests were used to assess performance. A CVT (Continuously Variable Transmission) Element-on-Ring Test was used to study metal/metal performance, and a VSFT (Variable Speed Friction Tester) procedure with cellulose based friction material was used to evaluate the μ-v (friction coefficient-velocity) clutch performance. Interestingly, a 400 TBN magnesium sulfonate detergent combined with a phosphorus containing friction modifier showed a special synergy.

Water-emulsified diesel fuel technology has been proven to reduce nitrogen oxides (NOx) and particulate matter (PM) simultaneously at relatively low cost compared to other pollution-reducing strategies. The value of this technology is that it requires absolutely no engine adjustments or modifications to reduce harmful emissions. Technologies that break the NOx -particulate trade-off are virtually non-existent, therefore understanding how the water contained in an emulsified fuel can reduce both NOx and PM simultaneously is critical. To understand this phenomenon, emulsified fuels with varying water levels (0 to 20%) were evaluated in a multi-cylinder marine engine using three different injection timings. This testing in an actual engine confirms that as the water level is increased the amount of NOx and PM are reduced without compromising engine performance.

A discriminating dynamometer-based test was developed for evaluating cold start and warmup engine performance based on in-cylinder pressure measurements. The dynamometer test offers advantages in time required, flexibility and reduced variability over the vehicle procedure on which it was based. A parametric study on fuel driveability index (DI), ethanol content and intake valve deposit (IVD) rating demonstrated that each of these parameters had a statistically significant impact on engine cold start performance. Simple numerical offsets to fitted models based on oxygen content of the fuel did not account for the difference in engine performance of hydrocarbon-only versus ethanol-containing fuels. The effect of IVD on engine performance did not appear to depend on the DI of the fuel. The benefits of cleaner valves are seen even in fuels of very low DI.

The lubricant is a key component in the successful operation of a manual transmission, but it is important that the interactive effects with the friction material are understood. This paper examines the effect of several key additive components on the friction and wear performance of a single sinter composition in a carefully controlled laboratory test. In addition, the test method allows one to develop information about the shift behavior of the fluid-synchronizer material combination which provides useful information about shift quality. From the original experimental design program a predictive model was developed and an optimized formulation was tested as a validation of the results.

Extended drain of axle and transmission lubricants has gained wide acceptance in both passenger car and commercial vehicle applications. Understanding how the lubricant changes during extended drain operations is crucial in determining appropriate lubricants and drain intervals for these applications. A suitable aging screen test with an established relationship to field performance is essential. Over the years numerous methods have been studied (DKA, GFC, ISOT, ASTM L-60) with varying degrees of success1,2,3. Current methods tend to be overly severe in comparison to field experience, hence the need for further work in this area. As a result of recent work, a lubricant aging test method has been developed which shows good correlation with field experience, giving us an effective tool in the development of long drain oils.

Requirements to reduce emissions and improve vehicle fuel economy continue to increase, spurred on by agreements such as the Kyoto Protocol. Lubricants can play a role in improving fuel economy, as evidenced by the rise in the number of engine oil specifications worldwide that require fuel economy improvements. A novel friction modifier technology has been developed to further improve vehicle fuel economy. The development of this novel friction modifier technology which contains only N,O,C,H was previously published along with the initial demonstration of performance in motorized Toyota engines. In order to validate this performance in fired engine tests, oil was evaluated in a Toyota Corolla Fielder with a 1500 cc gasoline engine. Testing was conducted in the Japanese 10-15 and JC08 modes, as well as the European EC mode, and the US FTP mode.

Specific frictional properties are essential to provide correct and pleasurable shifting in a manual transmission. Synchroniser rings are being manufactured from an increasingly wider range of materials, and it is important to understand synchroniser-additive interactions in order to develop tailored lubricants that provide the desired frictional performance. This paper describes a study of the interaction of various friction modifier additives with a range of synchroniser materials in order to better understand the potential to develop lubricants that provide optimal frictional performance across a wide range of manual transmission-synchroniser systems.

The use of a copper diesel fuel additive in an emission control system improves particulate oxidation. This expands the operability of available systems by reducing the particulate mass loading and related external energy consumption required during regeneration. Easier, more frequent regenerations improve overall engine/system efficiency and reduce thermal stress on filtration media. Procedures for optimizing additive use are presented. In addition, the results from a health study are reviewed.

The international Lubricant Standardization and Approval Committee (ILSAC) GF-2 specification requires Passenger Car Motor Oils to provide enhanced fuel economy in a modern low friction engine (ASTM Sequence VIA). In previous SAE publications the authors have studied the boundary lubrication regime and documented the impact of friction modifiers and antiwear additives on Sequence VIA fuel economy. This paper shifts the focus to the hydrodynamic lubrication regime and details fundamental studies of viscosity modifiers and base oils on fuel economy as measured by this low friction engine. The viscosity modifiers were found to have surprisingly little impact on this test, while moving to base oils of higher viscosity index improved fuel economy as might be theoretically expected. A study of formulating SAE 5W-30 motor oils with base oils of increasing viscosity index showed the optimum fuel economy was able to be obtained with a high viscosity index base stock.

This paper describes the development of a image analysis system that can be used to rate injectors from the Cummins L10 Injector Depositing Test. In the procedure, injectors are mounted on a computer controlled turntable and scanned using a CCD camera focused on the labyrinth flow area of the injector. The scanned monochrome images are processed and assigned an average gray scale rating. Results from the image analysis system are compared to the modified CRC Piston and Ring Rating method currently used within the Cummins test procedure. To do this, a series of injectors that have been rated by trained raters at a recent workshop were also rated via the image analysis system. The image analysis system ratings demonstrated a strong correlation (R = 0.85) to the CRC ratings. Using these same injectors, the image analysis method shows improvements in repeatability and reproducibility of approximately 50% over the current procedure.

The regenerative characteristics of a diesel particulate filter have been experimentally examined. The effect of particulate accumulation on system backpressure was of primary interest. To improve particulate regeneration, a copper compound was added to the fuel. The test results demonstrate that copper-containing fuel additives improve the regeneration characteristics of the filter, maintaining system backpressure at an acceptable level. Improved regeneration performance is expected to extend the operating range and life of the filter system. A model describing regeneration characteristics was developed to indicate the benefits of fuel copper concentration in controlling system backpressure.