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The operating conditions of a typical motorcycle are considerably different than those of a typical passenger car and thus require an oil capable of handling the unique demands. One primary difference, wet clutch lubrication, is already addressed by the current JASO four-stroke motorcycle engine oil specification (JASO T 903:2011). Another challenge for the oil is gear box lubrication, which may be addressed in part with the addition of a gear protection test in a future revision to the JASO specification. A third major difference between a motorcycle oil and passenger car oil is the more severe conditions an oil is subjected to within a motorcycle engine, due to higher temperatures, engine speeds and power densities. Scooters, utilizing a transmission not lubricated by the crankcase oil, also place higher demands on an engine oil, once again due to higher temperatures, engine speeds and power densities.

The Association des Constructeurs Européen d'Automobiles (ACEA) light duty diesel engine specifications requires a kinematic viscosity measurement technique for Peugeot XUD-11 BTE drain oils. This viscosity measurement is used to define the medium temperature dispersivity of soot in the drain oil.(1) This paper discusses the use of rotational rheology methods to measure the Newtonian character of XUD-11 drain oils. The calculation of the rate index using the Hershel Bulkley model indicates the level of non-Newtonian behavior of the drain oil and directly reflects the level of soot dispersion or agglomeration. This study shows that the more non-Newtonian the drain oil the greater the difference between kinematic and rotational viscosity measurements Oscillation (dynamic) rheological techniques are used to characterize build up of soot structure.

One of the key functions of lubricating oil additives in diesel engines is to control oil thickening caused by soot accumulation. Over the last several years, it has become apparent that the composition of the base oil used within the lubricant plays an extremely important role in the oil thickening phenomenon. In particular, oil thickening observed in the Mack T-8 test is significantly affected by the aromatic content of the base oil. We have found that the Mack T-8 thickening phenomenon is associated with high electrical activity, i.e., engine drain oils which exhibit high levels of viscosity increase show significantly higher conductivities. These findings suggest that electrical interactions are involved in soot-induced oil thickening.

The paper discusses the concept, design and final results from the ‘Ultra Boost for Economy’ collaborative project, which was part-funded by the Technology Strategy Board, the UK's innovation agency. The project comprised industry- and academia-wide expertise to demonstrate that it is possible to reduce engine capacity by 60% and still achieve the torque curve of a modern, large-capacity naturally-aspirated engine, while encompassing the attributes necessary to employ such a concept in premium vehicles. In addition to achieving the torque curve of the Jaguar Land Rover naturally-aspirated 5.0 litre V8 engine (which included generating 25 bar BMEP at 1000 rpm), the main project target was to show that such a downsized engine could, in itself, provide a major proportion of a route towards a 35% reduction in vehicle tailpipe CO2 on the New European Drive Cycle, together with some vehicle-based modifications and the assumption of stop-start technology being used instead of hybridization.

Life Cycle Assessment (LCA) is a methodology used to determine quantitatively the environmental impacts of a range of options. The environmental community has used LCA to study all of the impacts of a product over its life cycle. This analysis can help to prevent instances where a greater degree of environmental harm results when changes are made to products based on consideration of impacts in only part of the life cycle. This study applies the methodology to engine lubricants, and in particular chlorine limits in engine lubricant specifications. Concern that chlorine in lubricants might contribute to emissions from vehicle exhausts of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF), collectively called PCDD/F, led to the introduction of chlorine limits in lubricant specifications. No direct evidence was available linking chlorine in lubricants to PCDD/F formation, but precautionary principles were used to set lubricant chlorine limits.

A European test procedure for evaluating engine deposits, using the Mercedes Benz M111 bench engine, has already been approved for inlet valve deposits (IVD) and is under development for combustion chamber deposits (CCD) by the Co-ordinating European Council (CEC). This paper describes CCD effects on emissions using a slightly modified version of this engine test procedure and compares it with CCD/emissions data from road vehicles. The engine used was a modern four valve, four cylinder, 2.0 litre passenger car unit and the bench test procedure used extended the operating time from the specified 60 hours to 180 hours. The road vehicle trial used two Mercedes Benz C200 passenger cars fitted with the M111 engine and two Ford Mondeo 2.0 litre passenger cars. Data was collected up to 11200km, approximately equivalent to 180 hours operation of the bench engine.

Global emission legislations for diesel engines are becoming increasingly stringent. While the exhaust gas composition requirements for prior iterations of emission legislation could be met with improvements in the engine's combustion process, the next issue of European, North American and Japanese emission limits greater than 2005 will require more rigorous measures, mainly employment of exhaust gas aftertreatment systems. As a result, many American diesel OEMs are considering NOx adsorbers as a means to achieve 2007+ emission standards. Since the efficacy of a NOx adsorber over its lifetime is significantly affected by sulfur (“sulfur poisoning”), forthcoming reductions in diesel fuel sulfur (down to 15 ppm), have raised industry concerns regarding compatibility and possible poisoning effects of sulfur from the lubricant.

This study investigates the effects of octane quality on the performance, i.e., acceleration and power, and fuel economy (FE) of one late model US vehicle, which is powered by a small displacement, turbocharged, gasoline direct injection (GDI) engine. The relative importance of the gasoline parameters Research and Motor Octane Number (RON and MON) in meeting the octane requirement of this engine to run at an optimum spark timing for the given demand was considered by evaluating the octane index (OI), where OI = (1-K) RON + K MON and K is a constant depending on engine design and operating conditions. Over wide open throttle (WOT) accelerations, the average K of this Pontiac Solstice was determined as −0.75, whereby a lower MON would give a higher OI, a higher knock resistance and better performance.

The world is firmly focused on reducing energy consumption and on increasingly stringent regulations on CO2 emissions. Examples of regulatory changes include the new United States Environmental Protection Agency's (U.S. EPA) fuel economy test procedures which were required beginning with the 2008 model year for vehicles sold in the US market. These test procedures include testing at higher speeds, more aggressive acceleration and deceleration, and hot-weather and cold-temperature testing. These revised procedures are intended to provide an estimate that more accurately reflects what consumers will experience under real world driving conditions. The U.S.

With the continued growth of the sport utility vehicle (SUV) market in North America in recent years more emphasis has been placed on fluid performance in these vehicles. In addition to fuel economy the key performance area sought by original equipment manufacturers (OEMs) in general has been temperature reduction in the axle. This is being driven by warranty claims that show that one of the causes of axle failure in these type vehicles is related to overheating. The overheating is, in turn, caused by high load situations, e.g., pulling a large trailer at or near the maximum rated load limit for the vehicle, especially when the vehicle or its main subcomponents are relatively new. The excessive temperature generally leads to premature failure of seals, bearings and gears. The choice of lubricant can have a significant effect on the peak and stabilized operating temperature under these extreme conditions.

A predictive model for estimating the fuel saving of “top tier” engine, axle and transmission lubricants (compared to “mainstream” lubricants), in a heavy duty truck, operating on a realistic driving cycle, is described. Simulations have been performed for different truck weights (10, 20 and 40 tonnes) and it was found that the model predicts percentage fuel economy benefits that are of a similar magnitude to those measured in well controlled field trials1. The model predicts the percentage fuel saving from the engine oil should decrease as the vehicle load increases (which is in agreement with field trial results). The percentage fuel saving from the axle and gearbox oils initially decreases with load and then stays more or less constant. This behaviour is due to the detailed way in which axle and gearbox efficiency varies with speed/load and lubricant type.

It is expected that the world's energy demand will double by 2050, which requires energy-efficient technologies to be readily available. With the increasing number of vehicles on our roads the demand for energy is increasing rapidly, and with this there is an associated increase in CO₂ emissions. Through the careful use of optimized lubricants it is possible to significantly reduce vehicle fuel consumption and hence CO₂. This paper evaluates the effects on fuel economy of high quality, low viscosity heavy-duty diesel engine type lubricants against mainstream type products for all elements of the vehicle driveline. Testing was performed on Shell's driveline test facility for the evaluation of fuel consumption effects due to engine, gearbox and axle oils and the variation with engine operating conditions.

The demonstration benefit from fuel-borne fuel-economy additives to a precision of 1%, or better, traditionally requires very careful experimental design and considerable resource intensity. In practice, the process usually requires the use of well-defined drive cycles (e.g. emission certification cycles HFET, NEDC) in conjunction with environmentally-controlled chassis dynamometer facilities. Against this background, a method has been developed to achieve high-precision fuel economy comparison of gasoline fuels with reduced resource intensity and under arbitrary real-world driving conditions. The method relies upon the inference of instantaneous fuel consumption via the collection of OBD data and the simultaneous estimation of instantaneous engine output from vehicle dynamical behaviour.

Consumer demand for size, weight and horsepower has dictated a prominent role for sport utility vehicles and light trucks in the product lines of major North American automobile manufacturers. Inherently less efficient than passenger cars, these vehicles will be facing more stringent light duty CAFE (Corporate Average Fuel Economy) standards beginning in 2005 when mileage targets will be elevated to 21 mpg; this figure will be further increased to 22.2 mpg by 2007. In order to accommodate both public demand and CAFE requirements, vehicle manufacturers are seeking ways to improve fuel economy through design and material modifications as well as through improvements in lubrication. The axle lubricant may have an important impact on fuel economy, and axle lubricants can be tailored to deliver higher levels of operating efficiency over a wide range of conditions.

This paper outlines the history and background of the NLGI (formerly known as the National Lubricating Grease Institute) lubricating grease specifications, GC-LB classification of Automotive Service Greases as well as details on the development of new requirements for their High-Performance Multiuse (HPM) grease certification program. The performance of commercial lubricating grease formulations through NLGI's Certification Mark using the GC-LB Classification system and the recently introduced HPM grease certification program will be discussed. These certification programs have provided an internationally recognized specification for lubricating grease and automotive manufacturers, users and consumers since 1989. Although originally conceived as a specification for greases for the re-lubrication of automotive chassis and wheel bearings, GC-LB is today recognized as a mark of quality for a variety of different applications.

SAE 2004-01-3009 reported on work conducted to investigate the correlation between the Mack T-11 laboratory engine tests and vehicle field tests. It concluded that the T-11 test provides an effective screening tool to investigate soot-related viscosity increase, and the severity of the engine test limits provides a substantial margin of safety compared to the field. This follow-up paper continues the studies on the 2003 Mack CV713 granite dump truck equipped with an AI-427 internal EGR engine and introduces experimentation on a 2003 CX613 tractor unit equipped with an AC-460P cooled EGR engine. The paper further assesses the correlation of the field trials to the Mack T-11 engine test and reviews the impact of ultra low sulfur diesel (ULSD) and prototype CJ-4 lubricant formulations in these engines.

Soot related viscosity increase has been reported as a field issue in some diesel engines and this led to the development of the T-11 engine test, incorporated in the Mack EO-N Premium Plus 03 specification (014 GS 12037). This study compares T-11 laboratory engine tests and vehicle field tests and seeks to confirm the correlation between them. The findings are that the T-11 test provides an effective screening tool to investigate soot related viscosity increase, and the severity of the engine test limits gives a substantial margin of safety compared to the field. A complementary study was conducted in conjunction with this work that focuses on the successful application of electrochemical sensor technology to diagnose soot content and soot related viscosity increase. This will be the subject of a separate paper.

New technologies are being commercialized across the automotive industry to address demands for improved fuel economy, emissions reductions, and improved customer satisfaction. Push-belt continuously variable transmissions (b-CVTs) are beginning to command a significant percentage of the market now dominated by manual and conventional automatic transmissions. In addition, automobile manufacturers plan to introduce the first traction drive toroidal-CVTs to the market place within the next five years. A review of the relative benefits and limitations of each of these automatic transmissions exists in the literature. In this paper we consider how the performance requirements of each of these automatic transmission systems impact automatic transmission fluid technology. The physical characteristics and screen test performance of two commercial ATFs, a b-CVTF, and two traction fluids were examined.

Recently, research and testing of oxygenated diesel fuels has increased, particularly in the area of exhaust emissions. Included among the oxygenated diesel fuels are blends of diesel fuel with ethanol, or E diesel fuels. Exhaust emissions testing of E diesel fuel has been conducted by a variety of test laboratories under various conditions of engine type and operating conditions. This work reviews the existing public data from previous exhaust emissions testing on E diesel fuel and includes new testing performed in engines of varied design. Emissions data compares E diesel fuel with normal diesel fuel under conditions of different engine speeds, different engine loads and different engine designs. Variations in performance under these various conditions are observed and discussed with some potential explanations suggested.

Increasingly stringent fuel economy and emissions regulations around the world have forced the further optimization of nearly all vehicle systems. Many technologies exist to improve fuel economy; however, only a smaller sub-set are commercially feasible due to the cost of implementation. One system that can provide a small but significant improvement in fuel economy is the lubrication system of an internal combustion engine. Benefits in fuel economy may be realized by the reduction of engine oil viscosity and the addition of friction modifying additives. In both cases, advanced engine oils allow for a reduction of engine friction. Because of differences in engine design and architecture, some engines respond more to changes in oil viscosity or friction modification than others. For example, an engine that is designed for an SAE 0W-16 oil may experience an increase in fuel economy if an SAE 0W-8 is used.