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Despite the many years of widespread use of the BMW Intake Valve Deposit (IVD) vehicle test, relatively little has been published quantifying the variation in the test procedure. This paper presents an analysis of the variability in the BMW test. Though results from 8045 km (8K; 5,000 mile) tests rather than 16090 km (16K; 10,000 mile) are highlighted due to the size of the available database and relative sensitivity of the data, analysis suggests that variation at 8K is representative of 16K variation. A square root transformation of average deposit weight at 8K, though more cumbersome than the more common log transformation, is found to be the most appropriate way to eliminate the dependence of variation on the absolute level of deposits. Within-car variation is found to account for over half of the test-to-test variation, contradicting the notion that car-to-car differences are the dominant source of variability.

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.

In API engine oil licensing, candidate oils must meet the performance requirements of category defined engine tests. While API category engine tests are developed to target a theoretical performance standard, it is rare that the cost to test and approve oils is understood. Given that engine tests are an integral part of oil evaluation, understanding of engine test value is necessary. Therefore, measurements of value are presented as Unbiased Engine Test Evaluation (UETE). UETE evaluates an engine test's draw on time and money resources by estimating the average number of tests required before a candidate oil will pass the category defined engine tests. A pilot study using the API CH-4 Category is presented.

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).

Intentionally adding water to oil, in the laboratory, provides an indication of the oil's ability to tolerate the presence of water. Various characteristics, such as emulsion, haze or separation, may be observed. Some blends of oil and water have been shown to form structures when left undisturbed. A visual, qualitative, storage test is capable of detecting this phenomenon as the presence or absence of structure. However, the time frame of formation can be on the order of days or weeks and is sensitive to handling and temperature effects. Quantitative methods are required for any evaluation of chemistry, temperature and handling effects on the rate and strength of structure formation. This paper describes rheological and electrical methods which directly and indirectly measure the tendency to form a structure at the molecular level, yielding rate of formation and strength information.

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.

The relationship between 76 Racing and NASCAR allowed 76 Lubricants Company to work closely with Richard Childress Racing (RCR) and The Lubrizol Corporation in the development of oil screening and analytical test procedures which permit rapid evaluation of potential top-tier NASCAR race oils. The oils were designed to meet the challenge of increasingly severe engine operating parameters. This paper will discuss dynamometer testing and how properties of the oil such as viscosity grade, base fluid, and additives affect engine durability in the dynamometer test program and performance at the track in NASCAR Winston Cup Racing. Areas of growing concern include the cam/lifter contact, ring/liner contact, wrist pin/pin bore and wrist pin bushing contacts. Racing lubricants must withstand these harsh conditions for periods of 3-4 hours of continuous running.

Information relative to oil thickening has been developed in road tests. Typical operating temperatures, as well as the length of time required to thicken oils in these tests, are described. A laboratory test procedure has been developed that shows a good degree of correlation with this field service. The effect of test conditions such as jacket temperature and piston ring design on oil thickening in the laboratory are described.

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.

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.

Additives are an integral part of today's fuels. Together with carefully formulated base fuel composition, they contribute to efficiency, dependability and long life of gasoline and diesel engines. As a primer, this paper describes the range of chemical additives formulated for gasoline and diesel fuel and their effects. Specific functions and benefits of additives, typical use levels, and test methods for evaluation are discussed. Additive usage may be divided into three major categories: a) to satisfy desired levels of performance in engines, b) to insure delivery of uncontaminated, on-specification fuels to the end user and c) achieve necessary chemical/physical properties as manufactured by the refiner.

Additives are an integral part of today's fuels. Together with carefully formulated base fuel composition, they contribute to efficiency, dependability and long life of gasoline and diesel engines. As a primer, this paper describes the range of chemical additives formulated for gasoline and diesel fuel and their effects. Specific functions and benefits of additives, typical use levels, and test methods for evaluation are discussed. Additive usage may be divided into three major categories: a) to satisfy desired levels of performance in engines, b) to insure delivery of uncontaminated, on-specification fuels to the end user and c) achieve necessary chemical/physical properties as manufactured by the refiner.

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.

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.

Recent commercial specification revisions for automatic transmission fluids (ATFs) have focused upon more stringent friction requirements. More stringent friction durability characteristics are assessed using the SAE No. 2 tester. The commercial specifications do not include provisions to evaluate low speed friction characteristics, which have been shown to relate to torque converter shudder. This paper focuses upon effective use of the Falex 6 Multispecimen Tester to evaluate friction durability and to evaluate low speed friction characteristics in conjunction with low speed friction apparatus (LVFA) testing. Falex 6 testing agreed with torque fade observed in SAE No. 2 tests. Low speed stick-slip durability characteristics were effectively differentiated for a number of field ATFs. Falex 6 testing coupled with LVFA testing was shown to correlate with field experience and other test methods related to torque converter shudder.

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.

Accurate, timely field test results are necessary to develop and validate lubricants meeting frequently changing performance requirements. Field tests can also provide valuable information about performance deficiencies (e.g., soot related wear) which are not apparent in laboratory development tests. Since field tests are time intensive and increasingly expensive, it is imperative that the data generated provide meaningful results with reasonable expenditures. The data generation and analysis process are being constantly improved according to the principles of quality management. Part of the process improvement focuses on accurate, realistic treatment of the data since more variation is typically observed in field tests than in laboratory tests. One of the most difficult analytical processes occurs with oil consumption data.

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.

A test method has been developed which provides for the rapid measurement of the scuffing performance of diesel fuel using the Ball-On-Cylinder Lubricity Evaluator (BOCLE). A test can be completed in less than one hour. Data has been generated indicating that the method achieves good discrimination between fuels of varying lubricity and correlates well with fuel performance as measured in pump tests.

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.