Refine Your Search

Topic

Author

Search Results

Journal Article

Impact of Viscosity Modifiers on Gear Oil Efficiency and Durability: Part II

2013-04-08
2013-01-0299
This paper outlines the second part in a series on the effect of polymeric additives commonly known as viscosity modifiers (VM) or viscosity index improvers (VII) on gear oil efficiency and durability. The main role of the VM is to improve cold temperature lubrication and reduce the rate of viscosity reduction as the gear oil warms to operating temperature. However, in addition to improved operating efficiency across a broad temperature range compared to monograde fluids the VM can impart a number of other significant rheological improvements to the fluid [1]. This paper expands on the first paper in the series [2], covering further aspects in fluid efficiency, the effect of VM chemistry on these and their relationship to differences in hypoid and spur gear rig efficiency testing. Numerous VM chemistry types are available and the VM chemistry and shear stability is key to fluid efficiency and durability.
Technical Paper

Next Generation Torque Control Fluid Technology, Part IV: Using a New Split-μ Simulation Test for Optimizing Friction Material-Lubricant Hardware Systems

2010-10-25
2010-01-2230
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.
Journal Article

Impact of Lubricating Oil Condition on Exhaust Particulate Matter Emissions from Light Duty Vehicles

2010-05-05
2010-01-1560
Limited technical studies to speciate particulate matter (PM) emissions from gasoline fueled vehicles have indicated that the lubricating oil may play an important role. It is unclear, however, how this contribution changes with the condition of the lubricant over time. In this study, we hypothesize that the mileage accumulated on the lubricant will affect PM emissions, with a goal of identifying the point of lubricant mileage at which PM emissions are minimized or at least stabilized relative to fresh lubricant. This program tested two low-mileage Tier 2 gasoline vehicles at multiple lubricant mileage intervals ranging from zero to 5000 miles. The LA92 cycle was used for emissions testing. Non-oxygenated certification fuel and splash blended 10% and 20% ethanol blends were used as test fuels.
Technical Paper

Next Generation Torque Control Fluid Technology, Part III: Using an Improved Break-Away Friction Screen Test to Investigate Fundamental Friction Material-Lubricant Interactions

2010-10-25
2010-01-2231
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.
Technical Paper

A Comprehensive Examination of the Effect of Ethanol-Blended Gasoline on Intake Valve Deposits in Spark-Ignited Engines

2007-10-29
2007-01-3995
Ethanol-gasoline blends are widely understood to present certain technical challenges to engine operation. Despite widespread use of fuels ranging from E5 (5% ethanol in gasoline) in some European countries to E10 (10% ethanol) in the United States to E100 (100% ethanol; “alcool”) in Brazil, there are certain subjects which have only anecdotally been examined. This paper examines two such issues: the effect of ethanol on intake valve deposits (IVD) and the impact of fuel additive on filter plugging (a measure of solubility). The effect of ethanol on IVD is studied along two lines of investigation: the effect of E10 in a multi-fuel data set carried out in the BMW 318i used for EPA and CARB certification, and the effect of varying ethanol content from 0% to 85% in gasoline carried out in a modern flex-fuel vehicle.
Technical Paper

Are the Traditional Methods for Determining Depletion of Total Base Number Providing Adequate Engine Protection?

2007-10-29
2007-01-4001
With the increasing use of modern, EGR-equipped, heavy-duty diesel engines and the use of lower sulfur and alternate fuels, such as biodiesel, lubricants are being exposed to a range of different compositions of acids. To complement the traditional detergent bases, todays lubricants have evolved to include a higher proportion of basic materials from amine-derived sources to aid in oxidation and soot control. This paper explores the impact of the different sources of acids, some of the issues they create and how they can be addressed, exemplified in a prototype CJ-4 lubricant formulation.
Technical Paper

Development of Next-Generation Automatic Transmission Fluid Technology

2007-10-29
2007-01-3976
Global original equipment manufacturers (OEMs) have requested lower viscosity automatic transmission fluid (ATF) for use in conventional and 6-speed automatic transmissions (AT) to meet growing demands for improved fuel economy. While lower-viscosity ATF may provide better fuel economy by reducing churning losses, other key performance attributes must be considered when formulating lower viscosity ATF(1,2). Gear and bearing performance can be key concerns with lower-viscosity ATFs due to reduced film thickness at the surfaces. Long-term anti-shudder performance is also needed to enable the aggressive use of controlled slip torque converter clutches that permit better fuel economy. And, friction characteristics need to be improved for higher clutch holding capacity and good clutch engagement performance. This paper covers the development of next-generation, low-viscosity ATF technology, which provides optimum fuel economy along with wear and friction durability.
Technical Paper

Low Volatility ZDDP Technology: Part 2 - Exhaust Catalysts Performance in Field Applications

2007-10-29
2007-01-4107
Phosphorus is known to reduce effectiveness of the three-way catalysts (TWC) commonly used by automotive OEMs. This phenomenon is referred to as catalyst deactivation. The process occurs as zinc dialkyldithiophosphate (ZDDP) decomposes in an engine creating many phosphorus species, which eventually interact with the active sites of exhaust catalysts. This phosphorous comes from both oil consumption and volatilization. Novel low-volatility ZDDP is designed in such a way that the amounts of volatile phosphorus species are significantly reduced while their antiwear and antioxidant performances are maintained. A recent field trial conducted in New York City taxi cabs provided two sets of “aged” catalysts that had been exposed to GF-4-type formulations. The trial compared fluids formulated with conventional and low-volatility ZDDPs. Results of field test examination were reported in an earlier paper (1).
Technical Paper

Improved Friction Modifiers to Aid in Future Fuel Economy Targets

2007-10-29
2007-01-4134
Requirements to improve vehicle fuel economy continue to increase, spurred on by agreements such as the Kyoto Protocol. Lubricants can play a role in aiding fuel economy, as evidenced by the rise in the number of engine oil specifications that require fuel economy improvements. Part of this improvement is due to achieving suitable viscometric properties in the lubricant, but additional improvements can be made using friction modifier (FM) compounds. The use of FMs in lubricants is not new, with traditional approaches being oleochemical-based derivatives such as glycerol mono-oleate and molybdenum-based compounds. However, to achieve even greater improvements, new new friction modifying compounds are needed to help deliver the full potential required from next generation lubricants. This work looks at the potential improvements available from new FM technology over and above the traditional FM compounds.
Technical Paper

The Effect of Heavy Loads on Light Duty Vehicle Axle Operating Temperature

2005-10-24
2005-01-3893
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.
Technical Paper

Cloud Point Depressant Response Effects in Ultra-Low-Sulfur Diesel Fuel

2005-10-24
2005-01-3898
Cloud point depressants (CPD) have been successfully used for many years in low-sulfur diesel fuels. For over ten years, custom-designed, specialty polymer chemistry has enabled refiners to meet cloud point (CP) guidelines with substantially less kerosene. This translates into greater refined yields through cut-point adjustment upgrades and the potential for diverting kerosene to more lucrative market opportunities, such as jet fuel. The practice of cut-point downgrades to gas oil can be costly because diesel fuel generally has greater value. Kerosene dilutions have historically been as high as 30%-40% by volume with low-sulfur diesel fuels [1, 2]. While kerosene addition enables fuels to reach CP guidelines, it may negatively impact the fuel's energy content, cetane number, lubricity, flash point and density. Properly designed CP additives are able to substantially reduce or even eliminate the need for kerosene, thus substantially reducing refinery costs.
Technical Paper

The Development of Predictive Models for Non-Acidic Lubricity Agents (NALA) using Quantitative Structure Activity Relationships (QSAR)

2005-10-24
2005-01-3900
This study describes the use of Quantitative Structure Activity Relationships (QSAR) to develop predictive models for non-acidic Lubricity agents. The work demonstrates the importance of separating certain chemical families to give better and more robust equations rather than grouping a whole data set together. These models can then be used as important tools in further development work by predicting activities of new compounds before actual synthesis/testing.
Technical Paper

Breaking the Viscosity Paradigm: Formulating Approaches for Optimizing Efficiency and Vehicle Life

2005-10-24
2005-01-3860
The popularity of light trucks and sport utility vehicles (SUVs), coupled with growing consumer demand for vehicles with more size, weight and horsepower, has challenged the original equipment manufacturers' (OEM) ability to meet the Corporate Average Fuel Economy (CAFE) specifications due to the increased contribution of these vehicle classes on fleet averages. The need for improved fuel economy is also a global issue due to the relationship of reduced fuel consumption to reduced CO2 emissions. Vehicle manufacturers are challenged to match the proper fluid with the application to provide the required durability protection while maximizing fuel efficiency. Recent new viscosity classifications outlined under SAE J306 aid in more tightly defining options for lubricant choice for a given application. Changes to the SAE J306 viscosity classification define new intermediate viscosity grades, SAE 110 and SAE 190.
Technical Paper

Breaking the Viscosity Paradigm: Formulating Approaches for Optimizing Efficiency and Axle Life - Part II

2006-10-16
2006-01-3272
The popularity of light trucks and sport utility vehicles (SUVs), coupled with growing consumer demand for vehicles with more size, weight and horsepower, has increased the impact of these vehicle classes on the manufacturer's CAFE (Corporate Average Fuel Economy) numbers. Consumers often use light trucks and SUVs in applications such as prolonged towing at highway speeds, resulting in heavy loading and/or high operating temperatures in the axle. These conditions require superior axle lubricant protection, often provided by choosing a higher viscosity fluid (e.g., SAE 75W-140). Traditionally, the choice of these higher viscosity fluids for enhanced durability performance often results in reduced city-highway efficiency. This paper will describe the use of controlled axle dynamometer laboratory testing methods to develop fluids that maximize both fuel efficiency and durability performance across the wide spectrum of the new proposed viscosity classifications.
Technical Paper

Next Generation Torque Control Fluid Technology, Part I: Break-Away Friction Screening Test Development

2006-10-16
2006-01-3270
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 rates 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 in order 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 the development of a break-away friction screening test using a Full-Scale Low-Velocity Friction Apparatus (FS-LVFA). Additionally, we will illustrate how this screening test can be used to investigate the fundamental friction material-lubricant interactions that occur in continuously engaged limited slip differentials.
Technical Paper

Next Generation Torque Control Fluid Technology, Part II: Split-Mu Screening Test Development

2006-10-16
2006-01-3271
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.
Technical Paper

Soot-Related Viscosity Increase - Further Studies Comparing the Mack T-11 Engine Test to Field Performance

2005-10-24
2005-01-3714
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.
Journal Article

The Effect of Viscosity Index on the Efficiency of Transmission Lubricants

2009-11-02
2009-01-2632
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.
Technical Paper

The Use of Life Cycle Assessment with Crankcase Lubricants to Yield Maximum Environmental Benefit – Case Study of Residual Chlorine in Lubricant

2008-10-06
2008-01-2376
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.
Technical Paper

Balancing Extended Oil Drain With Extended Equipment Life

1996-05-01
961110
All automotive gear oils must satisfy a series of standard industry or Original Equipment Manufacturer (OEM) tests. These usually include bench, axle dynamometer, and field tests. However, product development testing must extend beyond satisfying standard test protocols. This is especially true as increased emphasis is placed on extending oil drain intervals and increasing equipment life in the face of greater performance demands through new heavy-duty vehicle designs. End-users ultimately benefit from extended oil drain intervals and increased equipment life. However, the effort to achieve both initiatives will prove successful only through careful development and selection of the proper performance additives and base fluids. Also, a broad focus must be maintained to satisfy all lubricant requirements. These requirements build on a solid base of standard features and include new features that stretch the current envelope of gear oil performance.
X