SAE TECHNICAL PAPER 961093 Effect ofEngine OilAnticorrosion Characteristics onMultiple WetDisk Brake inOff-road Dump Truck Masaki Mori Komatsu Ltd. Kazuhito Mukai DynaxCorp. Akiko Konishi, Ikuo Uchino, andSatoshi Ohkawa Komatsu Ltd. International Spring Fuels &Lubricants MeetingDearborn, Michigan May6-8,1996 400Commonwealth Drive, Warrendale, PA15096-0001 U.S.A. Tel:(412)776-4841 Fax:(412)776-5760 6(5,(6Downloaded from SAE International by University of Wisconsin - Madison , Monday, September 10, 2018Theappearance oftheISSN codeatthebottom ofthispage indicates SAE's consent thatcopies ofthepaper maybemade forpersonal orinternal useofspecific clients. Thisconsent isgiven onthecondition however, thatthecopier paya$7.00 perarticle copy feethrough theCopyright Clearance Center, Inc.Operations Center, 222 Rosewood Drive, Danvers, MA01923 forcopyirtg beyond thatpermitted bySections 107or108ofU.S.Copyright Law. Thisconsent does notextend toother kinds of copying such ascopying forgeneral distribution, foradvertising orpromotional purposes, forcreating newcollective works, orforresale. SAE routinely stocks printed papers foraperiod ofthree years following date of publication. Direct your orders toSAE Customer Sales andSatisfaction Department. Quantity reprint rates canbeobtained fromtheCustomer Sales andSatisfaction Department. Torequest permission toreprint atechnical paper orpermission tousecopyrighted SAEpublications inother works, contact theSAE Publications Group. Nopartofthispublication maybereproduced inanyform, inanelectronic retrieval system orotherwise, without theprior written permission ofthepublisher. ISSN 0148-7191 Copyright 1996 Society ofAutomotive Engineers, Inc. Positions andopinions advanced inthispaper arethose oftheauthor(s) andnot necessarily those ofSAE. Theauthor issolely responsible forthecontent ofthe paper. Aprocess isavailable bywhich discussions willbeprinted withthepaper if itispublished inSAETransactions. Forpermission topublish thispaper infullorin part, contact theSAE Publications Group. Persons wishing tosubmit papers tobeconsidered forpresentation orpublication through SAE should send themanuscript ora300word abstract ofaproposed manuscript to:Secretary, Engineering Meetings Board, SAE. Printed inUSA 96-0049 Downloaded from SAE International by University of Wisconsin - Madison , Monday, September 10, 2018961093 Effect ofEngine OilAnticorrosion Characteristics onMultiple WetDisk Brake inOff-road Dump Truck Masaki Mori Komatsu Ltd. Kazuhito Mukai Dynax Corp. Akiko Konishi, Ikuo Uchino, andSatoshi Ohkawa Komatsu Ltd. ABSTRACT Recently high copper concentration of used oilshasbeen frequently detected inour oilanalysis system, although anyexcessive wear ofthecopper parts intheengines and the power-train was notdetected. Wehave found thecopper comes from copper solder intheoil cooler. Thus wehave investigated thecopper corrosion characteristics of commercially available engine oilsand power-train oils ina laboratory test. Most power-train oils didnot show copper corrosion, however some engine oilsshowed large weight loss ofacopper test piece. Inafieldtestofoff-road dump trucks, we have found thatthecopper, dissolved intheoil, caused glazing andfriction reduction problem of thewetbrake paper disk. Toclarify theglazing mechanism ofthedisk, simulated bench tests andused oilanalysis have been conducted. THE PURPOSE OFTHIS PAPER istodescribe the copper corrosion characteristics of commercially available engine oils and to describe theeffect ofthecopper dissolved inthe oilonwetbrake paper disks. Komatsu OilandWear Analysis (KOWA) is usually conducted tomonitor and maintain machine conditions. Recently, high copper concentration ofused oilshasbeen frequentlydetected. Itcan be considered that multipurpose engine oilcompatibility withcopperparts haschanged. Thus wehave investigated the compatibility ofthe recent multipurpose engine oils inalaboratory test Fish[1]* reported thatdecomposed organic calcium salts of