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Carefully controlled intake valve deposit (IVD) cleanup testing is found to be an effective method for differentiating the effect of the deposit control additives on combustion chamber deposits (CCD). The IVD buildup procedure produces a consistent initial level of CCD that the cleanup additive, the additive of interest, continues to build on until the end of the cleanup test. This “end of cleanup” CCD is found to be as repeatable and differentiable a measurement as tests run under the more common “keep clean” type operation. While IVD cleanup testing induces a mid-test disturbance in the form of the end of buildup measurement, it aligns well with two key CCD protocols in terms of the higher additive treat rates used and the extended total test length. In an analysis of results from IVD cleanup tests run using four different engine/vehicle procedures on seven different additives, several findings stood out.

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.

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.

The work presented here is the second of two papers investigating the KA24E engine test. The first paper characterized the KA24E engine in terms of the physical and chemical operating environment it presents to lubricants. The authors investigated oil degradation and wear mechanisms, and examined the differences between the KA24E and the Sequence VE engine tests. It was shown that while the KA24E does not degrade the lubricant to the extent that occurs in the Sequence VE, wear could be a serious problem if oils are poorly formulated. This second paper examines the wear response of the KA24E to formulation variables. A statistically designed matrix demonstrated that the KA24E is sensitive to levels of secondary zinc dialkyldithiophosphate (ZDP), dispersant and calcium sulfonate detergent. This matrix also showed that the KA24E appears to have good repeatability for well formulated oils and is a reasonable replacement for the wear component of the Sequence VE.

The Nissan KA24E engine test is designated to replace the Ford Sequence VE engine test as the low temperature valve train wear requirement for ILSAC (International Lubricant Standardization and Approval Committee) GF-3. The KA24E (recently designated the Sequence IV A) represents much of the current world-wide material and design technology while retaining the sliding cam/follower contact found in earlier engine designs. The work presented here is the first of two reports. In this first report, the physical and chemical environment the KA24E engine presents a lubricant is characterized and compared to those of the Sequence VE engine. Valve train materials and wear modes are investigated and described. Although chemical analysis of drain oils indicate the KA24E procedure does not degrade the lubricant to the extent seen in the Sequence VE test, valve train wear appears to proceed in a similar manner in both tests.

Throughout the evolution of the automobile, passenger car motor oils have been developed to address issues of wear, corrosion, deposit formation, friction, and viscosity stability. As a result, the internal combustion engines are now developed with the expectation that the lubricants to be used in them will deliver certain performance attributes. Metallurgies, clearances, and built-in stresses are all chosen with certain expectations from the lubricant. A family of chemicals that has been universally used in formulating passenger car motor oils is zinc dithiophosphates (ZDPs). ZDPs are extremely effective at protecting highly stressed valve train components against wear failure, especially in engine designs with a sliding contact between cams and followers. While ZDPs' benefits on wear control are universally accepted, ZDPs have been identified as the source of phosphorus, which deactivates noble metal aftertreatment systems.

The development of new transmission designs continues to affect the vehicle market. Continuously variable transmissions (CVTs) remain one of the more recent designs that impact the vehicle market. A desire for high belt-pulley capacity has driven studies concentrating on metal-on-metal (M/M) friction as a function of the CVT fluid. This paper describes the statistical techniques used to optimize the fluid friction as a function of additive components in a bench-scale, three-element test rig.

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.

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.

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.

Direct injection spark ignition (DISI) engine technology offers tremendous potential advantages in fuel savings and is likely to command a progressively increasing share of the European passenger vehicle market in the future. A concern is its propensity to form deposits on the inlet valve. In extreme cases, these deposits can lead to poor drivability and deteriorating emission performance. This inlet valve deposit build up is a well-known phenomenon in DISI engines since even additised fuel cannot wash over the back of intake valves to keep them clean. Two lubricants and two fuels were tested in a four car matrix. One of the lubricants was a fluid specifically developed by Lubrizol for DISI technology; the other was a baseline oil meeting Ford lubricants requirements and was qualified to ACEA A1/B1/ ILSAC GF2 performance level. Similarly, a baseline fuel was tested against an additised system.

Mist generated from water-soluble fluids used in machining operations represents a potentially significant contribution to worker exposure to airborne particles. Part I of this study [1], discussed polymer additives as mist suppressants for straight mineral oil metalworking fluids (MWF), which have been successfully employed at several locations. This paper focuses on recent developments in polymer mist suppressants for water-based MWF, particularly in the production environment. The polymer developed and tested in this study functions on a similar basis to that for straight oil anti-mist additives. This water soluble polymer suppresses the formation of small mist droplets and results in a distribution of larger droplet sizes. These larger droplets tend to settle out near the point of machining, resulting in a significant decrease in the total airborne mist concentration.

The Lubricant Test Monitoring System (LTMS) is the calibration system methodology and protocol for North American engine oil and gear oil tests. This system, administered by the American Society for Testing Materials (ASTM) Test Monitoring Center (TMC) since 1992, has grown in scope from five gasoline engine tests to over two dozen gasoline, heavy duty diesel and gear oil tests ranging from several thousand dollars per test to almost one-hundred thousand dollars per test. LTMS utilizes Shewhart and Exponentially Weighted Moving Average (EWMA) control charts of reference oil data to assist in the decision making process on the calibration status of test stands and test laboratories. Equipment calibration is the backbone step necessary in the unbiased evaluation of candidate oils for oil quality specifications.

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.

This paper features the results of emission tests conducted on diesel oxidation catalysts, and the combination of diesel oxidation catalysts and water blend fuel (diesel fuel continuous emulsion). Vehicle chassis emission tests were conducted using an urban bus. The paper reviews the impact and potential benefits of combining catalyst and water blend diesel fuel technologies to reduce exhaust emissions from diesel engines.

Wet clutch friction devices are the primary means by which torque is transmitted through many of today's modern vehicle drivelines. These devices are used in automatic transmissions, torque vectoring devices, active on-demand vehicle stability systems and torque biasing differentials. As discussed in a previous SAE paper ( 2006-01-3271 - Next Generation Torque Control Fluid Technology, Part II: Split-Mu Screen Test Development) a testing tool was developed to correlate to full-vehicle split-mu testing for limited slip differential applications using a low speed SAE #2 friction test rig. The SAE #2 Split-Mu Simulation is a full clutch pack component level friction test. The purpose of this test is to allow optimization of the friction material-lubricant hardware system in order to deliver consistent friction performance over the life of the vehicle.

Wet clutch friction devices are the primary means by which torque is transmitted in many of today's modern vehicle drivelines. These devices are used in automatic transmissions, torque vectoring devices, active on-demand vehicle stability systems, and torque biasing differentials. As discussed in a previous SAE paper ( 2006-01-3270 - Next Generation Torque Control Fluid Technology, Part I: Break-Away Friction Slip Screen Test Development), a testing tool was developed to simulate a limited slip differential break-away event using a Full Scale-Low Velocity Friction Apparatus (FS-LVFA). The purpose of this test was to investigate the fundamental interactions between lubricants and friction materials. The original break-away friction screen test, which used actual vehicle clutch plates and a single friction surface, proved a useful tool in screening new friction modifier technology.

The popularity of SUVs and light trucks in North America, combined with the return to rear-wheel-drive cars globally, is significantly increasing the installation of torque control devices that improve vehicle stability and drivability. As with other driveline hardware, it is important to optimize the friction material-lubricant-hardware system to ensure that a torque control device provides consistent performance over the life of the vehicle. While there are many publications on friction tests relevant to automatic transmission fluids, the literature relating to torque control testing is not as well developed. In this paper, we will describe a split-mu vehicle test and the development of a split-mu screening test. The screening test uses the SAE#2 friction test rig and shows how results from this test align with those from actual vehicle testing.