This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Friction and Stick-Slip Durability Testing of ATF
Annotation ability available
Sector:
Language:
English
Abstract
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. Finally, a Variable Speed Friction Tester (VSFT) was developed to improve test method continuity and improve test quality.
Recommended Content
Authors
Citation
Ward, W., Sumiejski, J., Castanien, C., Tagliamonte, T. et al., "Friction and Stick-Slip Durability Testing of ATF," SAE Technical Paper 941883, 1994, https://doi.org/10.4271/941883.Also In
References
- Hiramatsu T. et al. “Control Technology of Minimal Slip-Type Torque Converter Clutch,” SAE 850460 1985
- Watts R. F. et al. “Prediction of Low Speed Clutch Shudder in Automatic Transmissions Using the Low Velocity Friction Apparatus,” 17 June 1990 7th International Colloquium Automotive Lubrication Technische Academie Esslinger Germany 1990
- Yoshizawa K. et al. “Proposal of New Criteria and Test Methods for the Dynamic Performance of ATF,” SAE 900810 1990
- Miyazaki M. et al. “Evaluation of Vibration-Preventive Properties of Lubricating Oils in Wet Friction Plates and Retention of Such Properties Using a Friction Tester,” SAE 881674 1988
- Nakada T. et al. “A Study of Additive Effects on ATF Frictional Properties Using New Test Methods,” SAE 902150 1990
- Ashikawa R. Naruse T. Kuroshina H. Matsuoka T. Adachi T. Nakayama T. “ATF Characteristics Required for the Latest Automatic Transmissions,” SAE Paper 932849
- Ward W. C. Copes R. G. “The Next ATF Challenge - Meeting Fuel Efficiency Needs and Providing Driver Satisfaction.” Proceedings of NPRA Annual Meeting 1993
- Ohtani Hiroko et al. “Prediction of Anti-Shudder Properties of Automatic Transmission Fluids Using Modified SAE No. 2 Machine,” SAE Paper 940821
- Lam Robert C. Chen Yih-Fand “Friction Material for Continuous Slip Torque Converter Applications: Anti-Shudder Considerations,” SAE Paper 941031
- DEXRON®-III Automatic Transmission Fluid Specification GM-6297M General Motors Corporation 1993
- A Specification for MERCON® Automatic Transmission Fluid Ford Motor Company 1992
- Fish Robert L. “Wet Friction Material -Some Modes of Failure and Methods of Correction,” SAE Paper 760664 1976
- Fish Robert L. Truncone Samuel A. “Tracking Wet Friction Performance Via Energy Dispersive X-ray Spectroscopy,” SAE Paper 941033 1994
- Osanai Hiroshi lkeda Kunihiko Kato Koji “Relations Between Temperature in Friction Surface and Degradation of Friction Materials During Engaging of Wet Friction Paper,” SAE Paper 900553 1990