SA E TECHNICAL PAPER SERIES Next Generation High Performance ATF for Slip-Controlled Automatic Transmission Takanori Kugimiya, Narihiko Yoshimura, Toshiaki Kuribayashi, and Jun'ichi Mitsui Tonen Corp. Fumio Ueda, Yasushi Ando, and Takanori Nakada Toyota Motor Corp. Hirobumi Ohira Esso Sekiyu K.K. Reprinted from: Lubricants for Passenger Car and Heavy Duty Diesel Engines (SP-1304) The Engineering Society eA =For Advancing IWobi\ity iYLIo(C~and Sea Air and Space. INTERNATIONAL International Fall Fuels & Lubricants Meeting & Exposition Tulsa, Oklahoma October 13-1 6,1997 400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (412)776-4841 Fax:(412)776-5760 Downloaded from SAE International by University Of Newcastle, Wednesday, August 08, 2018.. - . .. - Law. ~hisconsentdoesnote~endtodher~dn&ofoopyingsuchascopyingforgeneral ~,foradve~ngorpromWpurp~~e~,forcreatingnewcdlectiveworks, or for resale. SAE routinely stocks printed papers for a period of three years following date ofpublication. Direct yourordersto SAECustomer Sales and Satisfaction Department. AN SAEpapers, standards, and selected ~areaLstmi&andm~mlkeSAE GlObalM&iiyDamlza. No~ofthis~maybyrepmducedinmyfon, inane(ecbo~%c rebievatsystern orohwise, wimwlmephrwrittenpenissionoftheprblsher. Posmksandopnionsadvancedmthspaperare~othauthor(s)andnc4~ those01 SAE. Theaumorissdelv resDonsibleformecontentoftheuaDer. A~rocessis available by which discussions kill de printed with the paper if it k &iblished in SAE Transactiins. For permission to publish this paper in full or in part, contact the SAE PuMiiGmup. SemtaIY. ~nginaering~eetin&&wd~~~. PrinWdin USA Downloaded from SAE International by University Of Newcastle, Wednesday, August 08, 2018Next Generation High Performance ATF for Slip-Controlled Automatic Transmission Takanori Kugimiya, Narihiko Yoshimura, Toshiaki Kuribayashi, and Jun'ichi Mitsui Tonen Corp. Fumio Ueda, Yasushi Ando, and Takanori Nakada Toyota Motor Corp. Hirobumi Ohira Esso Sekiyu K.K. Copyright 1997 Society of Automotive Engineers. Inc. ABSTRACT A slipcontrolled lock-up clutch system is very efficient in improving the fuel economy of automatic transmission (AT) equipped vehicles. However, aspecial automatic transmission fluid (ATF) which combines an anti-shudder property with high torque capacity is required for this system. In this study, we established additive technology for ATF having a sufficient anti-shudder property and high torquecapacity. Based on the technology, new ATF: ATF-r4 was developed. It was confirmed in actual AT tests that ATF-T4 has excellent anti-shudder durability and high torque capacity. Furthermore, ATF-T4 has good SAE No.2 friction characteristics, oxidation stability, compatibility with materials (elastomers, nylons, etc.) and viscosity at low temperatures. INTRODUCTION The slipcontrolled lock-up clutch system was developed to improve fuel economy[l],[2]. In the case of a normal lock-up clutch without a slipcontrol system, the power loss in the torque converter can be reduced by transferring engine power directly to the transmission at high speeds when the fluctuation of engine power is small. However, the use of direct power transmission at lower speeds is limited due to the greater fluctuation of the engine power. In a slipcontrolled lock-up clutch system, the clutch is continuously slipping at low speeds in orderto prevent transferring the fluctuation of engine power tothe transmission. Therefore, this system can reduce the power loss in the torque converter not only at high speeds but also at low speeds[3]. This system may cause unstable self-excited vibration, socalled "shudder vibration," when the lock-up clutch is continuously slipped. The frictional property of ATF largely affects the shudder vibration[4],fj]. The property of ATF which can prevent the shuddervibration is called "anti-shudder property." It is generally said that an ATF wit