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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.

This paper is part one of a longer term comparison of viscosity modifier behavior in modern automotive gear oil (AGO) fluids and the impact of these properties on fluid efficiency and durability. This first installment will compare the rheological properties, including EHD film thickness and traction coefficients, of the fluids across broad operating temperature, shear and load regimes and correlate these findings with rig efficiency testing. The effects of traction, EHD film thickness and high shear rheology on operating temperature are well documented and it is of particular interest to determine the extent to which different viscosity modifiers can beneficially impact these properties compared to a Brightstock-based SAE 80W90 grade fluid. The efficiency improvements of a VM would be for naught if it were not sufficiently shear stable and so comparisons are made between shear stable VM technologies.

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.

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.

The International Lubricant Standardization and Approval Committee (ILSAC) GF-2 requirements for Passenger Car Motor Oils (PCMOs) will lower phosphorus limits from a maximum of 0.12% allowed by ILSAC GF-1 to a maximum of 0.10%. In effect, the ILSAC GF-2 phosphorus limit removes 17% of the most commonly used antiwear and antioxidant additive in current PCMOs, zinc dialkyldithiophosphate (ZDP). This paper outlines some work in ASTM Sequence V engine dynamometer tests to quantify the effect of reducing the ZDP on valve train wear and sludge formation. Engine data for the Sequence VE, the proposed Sequence VF, and the modified Sequence VE are presented. These three tests summarize the evolution of the Sequence V from the Sequence VE for GF-1 to the dual plug Sequence VE configuration for the GF-2 specification.

The proposed 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 (Sequence VIA). This paper details fundamental studies of lubricant effects on fuel economy as measured by this low friction engine. Several conventional friction modifiers were tested with surprising results. One ester friction modifier, Ester B, which provides excellent fuel economy improvement in the Sequence VI, was found to be detrimental to the Sequence VIA. A second ester friction modifier, Ester A, performed as expected. Additionally, two molybdenum compounds, which are reported to provide excellent fuel economy in the Sequence VI, showed no fuel economy benefit in the Sequence VIA.

The authors provide evidence indicating that oils meeting only the minimum requirements of API GL-5 do not always provide adequate gear protection, especially in severe duty applications. Increases in commercial vehicle power and loading have accentuated the need for oils of greater load carrying ability. A modified version of the standard L-37 test may help identify oils that possess superior durability and thermal characteristics. Future gear lubricants should provide improved fuel economy, increased manual transmission life; and frictional characteristics that allow noise free performance in limited slip differentials.

This paper provides an overview of gear lubrication related to automotive equipment. A brief background in various aspects of lubrication, including lubrication theory, lubricant evaluation, performance designations, and formulation technology, is presented. This information is designed to assist those involved in the selection of automotive gear lubricants.

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). The durability of this fuel economy improvement is becoming increasingly important and will be address in the successor to the Sequence VIA, the Sequence VIB, which is currently under development for ILSAC GF-3. Previous investigations have indicated that the choice of detergent system and friction modifier has a large impact on the fuel economy of a lubricant. As a result of a study undertaken to further investigate these effects in a 1994 Ford Crown Victoria running the EPA Federal Test Procedure, a significant impact on tailpipe emissions was discovered. Detergent system affected both regulated emissions (hydrocarbon (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) emissions), and non-regulated emissions (carbon dioxide emissions).

Modern agriculture has evolved dramatically over the past half century. To be profitable, farms need to significantly increase their crop yields, and thus there are amplified demands on farming equipment. Equipment duty cycles have been raised in scope and duration, as the required output of the agricultural industry to sustain a growing population has stimulated the need for further advances in effective productivity gains on the farm. The mainstay mechanical assistant to the farmer, the tractor, has also evolved with the changes in modern agriculture to meet the requirements of these newer tasks. Larger, more capable vehicles have been introduced to help farmers efficiently meet these demands. At the same time, the current generation of tractor diesel engine lubricants has facilitated high levels of performance in the agricultural equipment market for many years. This is a testament to the role modern lubricants play in productivity in such a critical industry.

To meet increasingly stringent emissions and fuel economy regulations, many Original Equipment Manufacturers (OEMs) have recently developed and deployed small, high power density engines. Turbocharging, coupled with gasoline direct injection (GDI) has enabled a rapid engine downsizing trend. While these turbocharged GDI (TGDI) engines have indeed allowed for better fuel economy in many light duty vehicles, TGDI technology has also led to some unintended consequences. The most notable of these is an abnormal combustion phenomenon known as low speed pre-ignition (LSPI). LSPI is an uncontrolled combustion event that takes place prior to spark ignition, often resulting in knock, and has been known to cause catastrophic engine damage. LSPI propensity depends on a number of factors including engine design, calibration, fuel properties and engine oil formulation. Several engine tests have been developed within the industry to better understand the phenomenon of LSPI.

Driven by global demands for improved fuel economy and reduced emissions, significant improvements have been made to engine designs and control systems, vehicle aerodynamics, and fuel quality. Improvements, such as the continuously slipping torque converter, have also been made to automatic transmissions to increase vehicle efficiency. Recently, belt-continuously variable transmissions (b-CVTs) have been commercialized with the promise of significant fuel economy improvements over conventional automatic transmissions. Automotive traction drive transmissions may soon join belt-CVTs as alternative automatic transmission technology. Much of the information reported in technical and trade publications has been on the mechanics of these traction drive systems. As automotive traction drives move closer to commercial reality, more attention must be given to the performance requirements of the automotive traction fluid.