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The increasing focus on automotive automatic transmission contamination levels needs to result in both dramatic manufacturing system changes and transmission filtration needs. This paper focuses on defining and quantifying automatic transmission contaminant levels and the filtration needed to remove this contaminant. Specific data are presented which quantify the particle count and gravimetric level of transmissions oil samples. The debris found from numerous used filter analyses is also presented. Representative transmission valve contaminant sensitivity data is then shown which highlights the deleterious effect contaminant has on transmission valve operation. This paper concludes with the particle removal efficiency of common transmission sump filters being shown to be unable to remove many of the most damaging particles which result in transmission valve sticking, wear, and general shift quality degradation. Recommendations for correcting this situation are presented.

Diesel engine lubricant filtration is relied upon to protect critical engine components against wear. The type of filtration and the efficiency of particle removal is vital to minimizing engine wear. This paper presents the results of a comprehensive study which characterized the correlation between engine dynamometer tests and eight different engine filtration configurations. The experimental filtration schemes were exhaustively tested according to the well known multipass test procedure, SAE J1858. A low level Surface Layer Activation (SLA) radioactive spot was deposited at six points throughout the tested engine. Controlled, pressurized 0-30 micron test dust in an engine oil suspension was injected into the test engine under prescribed conditions and the progressive wear was measured at all the six points for four of the experimental filtration setups.

Rapid development of automotive fuels has occurred in the past ten to fifteen years resulting in reformulated and alternative liquid fuels together with a myriad of fuel additives aimed primarily at improving combustion and tail pipe emissions. Many of these changes have had significant but unreported or unmeasured effects on the physical properties of the fuels. This paper presents the details of a program which sought to characterize the lubricity (or antiwear) characteristics of known gasoline formulations with a bench top assessment test machine and to correlate these results to actual fuel pump wear debris generation tests.

This paper reports on a study that investigated the effect of composite contaminants on the wear of ball type valves. The objective was to develop a contamination control theory for predicting valve contaminant service life based on various mixture ratios of a silica test contaminant and a ferrous test contaminant. Filter specifications were determined which ensure valve contaminant service life. Theoretical considerations drew on contamination control theory and new relationships are introduced which account for ball valve wear due to two contaminants. Experimental tests were conducted with the Zeta test machine to establish particle abrasivity ratings and with the valve contaminant test stand to determine valve pressure degradation to contamination. It was found that less abrasive particles result in less valve performance degradation. This result substantiated the theoretical expressions relating the valve wear composite contaminant sensitivity coefficients.

The analysis and description of field generated containment in fluid systems (hydraulic or lubricating oil, fuels, water, etc.) continues to be one of the best indicators of system “health.” The monitoring of the contaminant provides an effective health measure by accurate determination of the contributing factors to system degradation. These include solid particles, water, additive depletion, and a host of resultant synergistic effects such as sludges, gels, etc. Their are many options available for field fluid analysis. Five specific analyses have been found to provide an extensive description of field contaminants. They are particle counting, gravimetric level analysis, proton induced X-ray emission (PIXE) analysis, ferrographic wear debris analysis, and water content analysis. Thorough descriptions of this procedures is provided with detailed application considerations.

This paper details an extensive study that was performed to define, quantify, and describe the contaminant found in automotive type transmissions. The results from the study were used to manufacture a new commercially available test contaminant that simulates the contaminant found in high mileage transmissions. The study was undertaken because no commercially available contaminant existed to test transmission related components, especially valves, pumps and filters. Most accepted test contaminants such as AC Fine or Course Test Dust were known not to give representative contaminant related results. The study consisted of collecting 29 oil samples from various mileage vehicles. The particle size distribution, gravimetric level, and chemical composition were found from the samples.