SA E TECHNICAL PAPER SERIES Prediction of Anti-Shudder Properties of Automatic Transmission Fluids using a Modified SAE No. 2 Machine Hiroko Ohtani, Rolfe J. Hartley, and Dennis W. Stinnett Ethyl Petroleum Additives, Inc. The Engineering Society =For Advancing Mobility and Sea Air and Space.. International Congress & Exposition Detroit, Michigan February 28-March 3,1994 400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (41 2)776-4841 Fax:(412)776-5760 Downloaded from SAE International by North Carolina State Univ, Tuesday, September 18, 2018The appearance of the ISSN code at the bottom of this page indicates SAE's consent that copies of the paper may be made for personal or internal use of specific clients. Thisconsent is given on the condition, however, that thecopier paya$5.00per article copy fee through the Copyright Clearance Center, Inc. Operations Center, 222 Rosewood Drive, Danvers, MA 01 923forcopying beyond that permitted by Sections 107 or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying such as copying for general distribution, for advertising or promotional purposes, for creating new collective works, or for resale. SAE routinely stocks printed papers for a period of three years following date of publication. Direct your orders to SAE Customer Sales and Satisfaction Department. Quantity reprint rates can be obtained from the Customer Sales and Satisfaction Department. To request permission to reprint a technical paper or permission to use copyrighted SAE publications in other works, contact the SAE Publications Group. All SAE papers, standards, and selected books are abstracted and indexed in the Global Mobility Database. No part of this publication may by reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. ISSN 0148-7191 Copyright 1994 Society of Automotive Engineers, Inc. Positions and opinions advanced in this paper are those of the author(s) and not necessarily those of SAE. The author is solely responsible for the content of the paper. A process is available by which discussions will be printed with the paper if it is published in SAE transactions. For permission to publish this paper in full or in part, contact the SAE Publications Group. Persons wishing to submit papers to be considered for presentation or publication through SAE should send the manuscript or a 300 word abstract of a proposed manuscript to: Secretary, Engineering Activity Board, SAE. Printed In USA oo1203~1~ Downloaded from SAE International by North Carolina State Univ, Tuesday, September 18, 2018Prediction of Anti-Shudder Properties of Automatic Transmission Fluids using a Modified SAE No. 2 Machine Hiroko Ohtani, Rolfe J. Hartley, and Dennis W. Stinnett Ethyl Petroleum Additives, Inc. ABSTRACT One of the barriers to successful implementation of the continuous slip torque converter clutch (CSTCC) design for automatic transmissions (AT) is transmission shudder. An important factor contributing to shudder is the frictional characteristics of the automatic transmission fluid (ATF). In this paper, we report the development of a test that allows the precise measurement of the frictional characteristics of the ATF at different sliding speeds (p-v data) using an SAE No. 2 friction machine. A conventional SAE No. 2 machine was modified, by installing a DC static drive motor, to simulate the sliding speeds, surface pressures, and fluid temperatures found in actual vehicle operating conditions. The p-v data obtained with the machine showed good correlation with the vehicle shudder, i.e., the ATFs showing more negative gradient in the p-v data caused more severe shudder in the vehicle. Initial shudder and anti-shudder durability evaluations were conducted using a variety of commercial and experimental ATFs. It was found that the highly friction-modified ATFs e