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Lubricants Formulation Technology for Fuel Saving Performance in Automatic Transmissions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published September 01, 2015 by SAE International in United States
Annotation ability available
The use of Automatic Transmission Fluids (ATFs) with lower viscosity and excellent anti-shudder durability for wet clutch system will be effective for improving fuel saving performance in automatic transmissions. In this study, two ATF formulation techniques were examined. The first trial formulation is to improve fatigue life in gear components even if a lower viscosity ATF is used. The second one is to improve anti-shudder durability for wet lock-up clutch system in AT units. As to fatigue life performance, the relation between molecular weight of Viscosity Index Improver (VII) and film formation property in EHL contact regions were experimentally investigated. ATFs containing VIIs with lower molecular weight tend to increasing EHL film thickness, resulting in a longer gear pitting fatigue life. Calcium detergents and ashless friction modifiers in ATFs were found to give a great impact on the anti-shudder performance. The trial ATF containing these additives demonstrated 1.5 times longer anti-shudder durability compared with a commercial ATF.
|Technical Paper||Friction and Stick-Slip Durability Testing of ATF|
|Technical Paper||A New Automatic Transmission Fluid with Extended Friction Durability and Minimal Temperature Dependence|
|Technical Paper||Part of the Year: Transmission Carrier|
CitationYokomizo, M., Iwai, T., Narita, K., and Kudo, M., "Lubricants Formulation Technology for Fuel Saving Performance in Automatic Transmissions," SAE Technical Paper 2015-01-2037, 2015, https://doi.org/10.4271/2015-01-2037.
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