400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (724) 776-4841 Fax: (724) 776-5760 SAE TECHNICAL PAPER SERIES 2001-01-0867 Automatic Transmission Hydraulic System Cleanliness – The Effects of Operating Conditions, Measurement Techniques and High-Efficiency Filters Pierre Nieuwland NTZ Nederland BV. Timothy A. Droste Powertrain Operations, Ford Motor Co. Reprinted From: Transmission and Driveline Systems Symposium 2001 (SP–1598) SAE 2001 World Congress Detroit, Michigan March 5-8, 2001Downloaded from SAE International by University of Michigan, Saturday, July 28, 2018The appearance of this 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. This consent is given on the condition,however, that the copier pay a $7.00 per article copy fee through the Copyright Clearance Center, Inc.Operations Center, 222 Rosewood Drive, Danvers, MA 01923 for copying beyond that permitted by Sec-tions 107 or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying such ascopying 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. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior wr itten permission of the publisher. ISSN 0148-7191 Copyright 2001 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 p ublished 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 3 00 word abstract of a proposed manuscript to: Secretary, Engineering Meetings Board, SAE. Printed in USAAll SAE papers, standards, and selected books are abstracted and indexed in theGlobal Mobility DatabaseDownloaded from SAE International by University of Michigan, Saturday, July 28, 20182001-01-0867 Automatic Transmission Hydraulic System Cleanliness – The Effects of Operating Conditions, Measurement Techniques and High-Efficiency Filters Pierre Nieuwland NTZ Nederland BV. Timothy A. Droste Powertrain Operations, Ford Motor Co. Copyright © 2001 Society of Automotive Engineers, Inc. ABSTRACT Malfunction due to solid particle contamination can be separated into two types. Type I malfunctions involve large particles (>150 micron), most often the remnants of manufacturing, and generally lead to early life repairs. Type II contamination includes much smaller particles (<50 micron), most of which are either generated wear debris, or particles ground up from larger Type I debris. These Type II particles are responsible for erratic valve performance, poor cooling and lubrication, and the accelerated degradation of Automatic Transmission Fluid (ATF), all of which promote transmission mid-life failures. This paper focuses on Type II contamination only. Hydraulic system cleanliness has a significant impact on shift timing, feel and general transmission durability. In order to manage the system cleanliness, a uniform repeatable measurement system must be available. Further, the effects of operating conditions must be known and considered. Once operating effects are accounted for, and re