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Investigation of Failure Modes in the DEXRON® III-H GM Cycling and Oxidation Tests
Technical Paper
2005-01-3891
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
To develop an automatic transmission fluid (ATF) that meets DEXRON® III-H specifications, the ATF must pass two critical tests, the GM oxidation test (GMOT) and the GM cycling test (GMCT), in addition to many other performance tests. The specification on the GMOT is that delta TAN (difference in total acid number compared with the fresh oil) at the end of the test does not exceed 3.25 while the specifications on GMCT are that delta TAN cannot exceed 2.0 and the 1-2 shift time must stay between 0.30 and 0.75 seconds throughout the test. For this work, we analyze oil oxidation and changes in oils' surface tension, drum and band surface degradation and deposit formation. We have found that with respect to the delta TAN limits of the DEXRON® III-H specification, the GMCT is more severe than the GMOT. The effect of base oil chemistry on oxidation in these tests has been quantified. Oil oxidation is not responsible for the GMCT 1-2 shift time increase. There are two failure modes identified to be responsible for the GMCT 1-2 shift time increase. One is an increase in air dispersed in the oils as they age and the other is thermal degradation of the band friction material. The surface tension of oils decreases as they are aged in the GMCT and the decrease in surface tension is correlated to an increase in 1-2 shift time. As surface tension decreases more air can be dispersed in an oil. As band friction materials are aged the decomposition temperature of the band material (as measured by pressure differential scanning calorimeter (PDSC)) decreases. The drop in PDSC decomposition temperature is associated with the degradation of the band friction material due to oligomerization caused by thermal effects rather than deposit or glazing of the friction material.
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Baren, R., Devlin, M., Tersigni, S., and Jao, T., "Investigation of Failure Modes in the DEXRON® III-H GM Cycling and Oxidation Tests," SAE Technical Paper 2005-01-3891, 2005, https://doi.org/10.4271/2005-01-3891.Also In
References
- General Motors Automatic Transmission Fluid Specification GM10055 June 2003
- Watts, R.F. Noles, J.R. Pujara, N. Trautman, T.R. 2001 “The Impact of Evolving Automatic Transmission Fluid Specifications on Base Oil Selection” SAE Paper No. 2001-01-1992
- Mack, P.D. Zaugg, T.D. Cohen, S.C. 1996 “Severely Hydro-cracked/Hydro-Isomerized base Oils-The Key to Enhanced Performance Levels” NPRA Paper FL-96-114
- Lok, B.K. Krug, R.R. Lee, S.K. Wilson, M.W. Lopez, J. 1996 “Cost Effective Mineral Oils with Synthetic Performance” Paper No. 67D AICHE Spring Meeting New Orleans 1996
- Henderson, H.E. Swinney, B. 1998 “High Quality Base Oils for Next Generation Automatic Transmission Fluids” SAE Paper No. 982666
- Gatto, V.J. Grina, M.A. Ryan, H.T. 2000 “The Influence of Chemical Structure on the Physical and Performance Properties of Hydrocracked Basestocks and Polyalphaolefins” Proceddings of the 12 th International Colloquium on Tribology Esslingen, Germany 2000
- Guan, J.J. Willermet, P.A. Carter, R.O. Melotik, D.J. 1998 “Interaction between ATFs and Friction Material for Modulated Torque Converter Clutches” SAE Paper No. 981098
- Dzidic, I. Petersen, H.A. Wadsworth, P.A. Hart, H.V. 1992 “Townsend Discharge Nitric Oxide Chemical Ionization Gas Chromatography/Mass Spectrometry for Hydrocarbon Analysis of the Middle Distillates” Analytical Chemical 64 2227
- Myers, R.H. Montgomery, D.C. 1995 “Response Surface Methodology: Process and Product Optimization Using Designed Experiments” John Wiley and Sons Inc.
- Choi, D.S. Jhon, M.S. Eyring, H. 1970 “Curvature Dependence of the Surface Tension and the Theory of Solubility” J. Chem. Phys. 53 1 2608 2614
- Tipton, C.D. Schiferl, E.A. 1997 “Fundamental Studies on ATF Friction, Part I” SAE Paper No. 971621
- Tohyama, M. Ohmori, T. Ueda, F. 1999 “Anti-Shudder Mechanism of ATF Additives at Slip-Controlled Lock Up Clutch” SAE Paper No. 1999-01-3616
- Schramm, L. L. Wassmuth, F. 1994 In Foams: Fundamentals and Applications in the Petroleum Industry Schramm L.L. Advances in Chemistry Series 242 American Chemical Society Washington, DC 9
- Fitch, J. 2002 “The Surface Tension Test - Is It Worth Resurrecting?” Practicing Oil Analysis Magazine September 2002
- Li, S Devlin, M. Tersigni, S.H. Jao, T.C. Yatsunami, K. Cameron, T.M. 2003 SAE Paper No. 2003-01-1983 Fundamentals of Anti-Shudder Durability: Part 1: Clutch Plate Study