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Friction Characteristics of Controlled-Slip Differential Lubricants
ISSN: 0148-7191, e-ISSN: 2688-3627
Published February 01, 1966 by SAE International in United States
Annotation ability available
Controlled-slip differentials (CSD) improve car operation under wheel slipping conditions. The performance of CSD's is dependent upon two criteria associated with clutch friction: “chatter” and “effectiveness.” “Chatter” is an undesirable noise which may occur during differential action. “Effectiveness” is a measure of the ability of the CSD clutches to transfer torque, during wheel slippage, to the wheel with the greater traction. The objective of this investigation was to definitely establish the cause of chatter, measure CSD effectiveness, and relate friction characteristics of lubricants to CSD operation.
In tests with an instrumented car, it was found that both chatter and effectiveness are strongly influenced by the lubricant. Chatter occurred with lubricants that produced an increase in clutch friction with decreasing sliding speed. Chatter did not occur with lubricants containing friction modifiers which produced a decrease in clutch friction with decreasing sliding speed. Unfortunately, these friction modifiers also reduced the CSD effectiveness by reducing the clutch friction.
To simulate CSD clutch plate sliding under more closely controlled laboratory conditions, the R-H Friction Apparatus was built. Results with this apparatus were correlated with those obtained with the car. Also, deterioration of CSD lubricant friction characteristics in car service was confirmed with the R-H Friction Apparatus.
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CitationHaviland, M., Goodwin, M., and Rodgers, J., "Friction Characteristics of Controlled-Slip Differential Lubricants," SAE Technical Paper 660778, 1966, https://doi.org/10.4271/660778.
- Automotive Industries Statistical Issue, Vol. 124, No. 6, March 15, 1961.
- Automotive Industries Statistical Issue, Vol. 134, No. 6, March 15, 1966.
- Allen J. W, “Modem Automotive Gear Lubricants.” Paper presented at 18th Annual Meeting of Independent Oil Compounders Association, October 1965.
- Lewis R. P. and O'Brien L. J., “Limited Slip Differentials.” SAE Transactions , Vol. 67 (1959), 203-212.
- Dinsmore D. W. and Smith A. H., “Multifunctional Friction - Modifying Agents.” Lubrication Engineering. September 1964.
- Haviland M. L and Rodgers J. J., “Friction Characteristics of Automatic Transmission Fluids as Related to Transmission Operation.” Lubrication Engineering, Vol. 17, No. 3 (March 1961), 110-117.
- Rodgers J. J. and Haviland M. L., “Friction of Transmission Clutch Materials as Affected by Fluids, Additives, and Oxidation.” Paper 194A presented at SAE Summer Meeting, Chicago, June 1960.
- Doyle W. P., Henry C. J. and Thomas P. R., “A Fundamental Study of Antisquawk Agents.” Paper presented at SAE Fuels and Lubricants Meeting, Tulsa, October 1963.