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400COMMONWEALTHDRIVE,WARRENDALE,PA150960001USATEL7247764841FAX7247765760WEBWWWSAEORGSAETECHNICALPAPERSERIES2002011691DEVELOPINGNEXTGENERATIONAXLEFLUIDSPARTITESTMETHODOLOGYTOMEASUREDURABILITYANDTEMPERATUREREDUCTIONPROPERTIESOFAXLEGEAROILSEDWARDSAKUCEWICH,JAMESNVINCI,FARRUKHSQURESHIANDROBERTWCAINTHELUBRIZOLCORPORATIONINTERNATIONALSPRINGFUELSLUBRICANTSMEETINGEXHIBITIONRENO,NEVADAMAY69,2002THEAPPEARANCEOFTHISISSNCODEATTHEBOTTOMOFTHISPAGEINDICATESSAESCONSENTTHATCOPIESOFTHEPAPERMAYBEMADEFORPERSONALORINTERNALUSEOFSPECIFICCLIENTSTHISCONSENTISGIVENONTHECONDITION,HOWEVER,THATTHECOPIERPAYAPERARTICLECOPYFEETHROUGHTHECOPYRIGHTCLEARANCECENTER,INCOPERATIONSCENTER,222ROSEWOODDRIVE,DANVERS,MA01923FORCOPYINGBEYONDTHATPERMITTEDBYSECTIONS107OR108OFTHEUSCOPYRIGHTLAWTHISCONSENTDOESNOTEXTENDTOOTHERKINDSOFCOPYINGSUCHASCOPYINGFORGENERALDISTRIBUTION,FORADVERTISINGORPROMOTIONALPURPOSES,FORCREATINGNEWCOLLECTIVEWORKS,ORFORRESALEQUANTITYREPRINTRATESCANBEOBTAINEDFROMTHECUSTOMERSALESANDSATISFACTIONDEPARTMENTTOREQUESTPERMISSIONTOREPRINTATECHNICALPAPERORPERMISSIONTOUSECOPYRIGHTEDSAEPUBLICATIONSINOTHERWORKS,CONTACTTHESAEPUBLICATIONSGROUPNOPARTOFTHISPUBLICATIONMAYBEREPRODUCEDINANYFORM,INANELECTRONICRETRIEVALSYSTEMOROTHERWISE,WITHOUTTHEPRIORWRITTENPERMISSIONOFTHEPUBLISHERISSN01487191COPYRIGHT2002SOCIETYOFAUTOMOTIVEENGINEERS,INCPOSITIONSANDOPINIONSADVANCEDINTHISPAPERARETHOSEOFTHEAUTHORSANDNOTNECESSARILYTHOSEOFSAETHEAUTHORISSOLELYRESPONSIBLEFORTHECONTENTOFTHEPAPERAPROCESSISAVAILABLEBYWHICHDISCUSSIONSWILLBEPRINTEDWITHTHEPAPERIFITISPUBLISHEDINSAETRANSACTIONSFORPERMISSIONTOPUBLISHTHISPAPERINFULLORINPART,CONTACTTHESAEPUBLICATIONSGROUPPERSONSWISHINGTOSUBMITPAPERSTOBECONSIDEREDFORPRESENTATIONORPUBLICATIONTHROUGHSAESHOULDSENDTHEMANUSCRIPTORA300WORDABSTRACTOFAPROPOSEDMANUSCRIPTTOSECRETARY,ENGINEERINGMEETINGSBOARD,SAEPRINTEDINUSAALLSAEPAPERS,STANDARDS,ANDSELECTEDBOOKSAREABSTRACTEDANDINDEXEDINTHEGLOBALMOBILITYDATABASEABSTRACTLIGHTTRUCKSANDSPORTUTILITYVEHICLESSUVSHAVEBECOMEEXTREMELYPOPULARINTHEUNITEDSTATESINRECENTYEARS,BUTTHISSHIFTTOLARGERPASSENGERVEHICLESHASPLACEDNEWDEMANDSUPONTHEGEARLUBRICANTTHEKEYCHALLENGEFACINGVEHICLEMANUFACTURERSINNORTHAMERICAISMEETINGGOVERNMENTMANDATEDFUELECONOMYREQUIREMENTSWHILEMAINTAININGDURABILITYGEAROILSMUSTPROVIDELONGTERMDURABILITYANDOPERATINGTEMPERATURECONTROLINORDERTOINCREASEEQUIPMENTLIFEUNDERSEVERECONDITIONSWHILEMAINTAININGFUELEFFICIENCYTHISPAPERDESCRIBESTHEDEVELOPMENTOFAFULLSCALELIGHTDUTYAXLETESTTHATSIMULATESAVARIETYOFDIFFERENTDRIVINGCONDITIONSTHATCANBEUSEDTOMEASURETEMPERATUREREDUCTIONPROPERTIESOFGEAROILFORMULATIONSTHEWORKPRESENTEDHEREOUTLINESATESTMETHODOLOGYTHATALLOWSGEAROILFORMULATIONSTOBECOMPAREDWITHEACHOTHERWHILEACCOUNTINGFORAXLECHANGESDUETOWEARANDCONDITIONINGDURINGTESTINGRESULTSARESHOWNFROMAVARIETYOFDIFFERENTAXLECONFIGURATIONSANDLOADINGCONDITIONSTHISTESTMETHODSHOWSTHEIMPORTANCEOFACCOUNTINGFORCHANGESINTHEAXLEWHENCOMPARINGTESTRESULTSWHENEVERSEVERECONDITIONSAREEXPERIENCEDINTRODUCTIONWITHINTHELASTFEWYEARS,THEREHASBEENARENEWEDDESIRETOMAKEFUELECONOMYIMPROVEMENTSINNORTHAMERICASLIGHTTRUCKSANDSPORTUTILITYVEHICLESSUVSVEHICLEMANUFACTURERSHAVESETAGGRESSIVEFUELEFFICIENCYIMPROVEMENTOBJECTIVESFORTHESEVEHICLESBECAUSEOFTHIS,GEARLUBRICANTSHAVEBEENTARGETEDTOCONTRIBUTEFUELECONOMYIMPROVEMENTSOVERTHECURRENTPRODUCTSUSEDINTHESEAPPLICATIONSTHISISNOTASEASYASITMAYSEEMINADDITIONTOACCEPTABLEFUELECONOMY,GEARLUBRICANTSAREREQUIREDTOPROTECTAXLECOMPONENTSUNDERAVARIETYOFSTRESSEDCONDITIONSTHESEINCLUDEHIGHSPEEDSCUFFING,LOWSPEED,HIGHTORQUEWEAR,CORROSIONANDOXIDATIONINLIGHTTRUCKANDRACINGAPPLICATIONS,GEAROILSMUSTPROVIDELONGTERMDURABILITYANDOPERATINGTEMPERATURECONTROLUNDEREXTREMECONDITIONS,SUCHASTRAILERTOWINGOREXTENDEDHIGHSPEEDAPPLICATIONSHIGHEROPERATINGTEMPERATURESFORPROLONGEDPERIODSCANADVERSELYAFFECTMETALLURGICALPROPERTIESANDREDUCEFLUIDFILMTHICKNESS,BOTHOFWHICHCANLEADTOPREMATUREEQUIPMENTFAILURESINOURVIEW,OPERATINGTEMPERATUREISANIMPORTANTINDICATOROFDURABILITYWHILEFUELECONOMYISNOWTHEDRIVINGFORCEINNEXTGENERATIONLUBRICANTDEVELOPMENT,ITISCLEARLYRECOGNIZEDTHATANYIMPROVEMENTSINFUELECONOMYMUSTNOTBEATTHEEXPENSEOFAXLEDURABILITYORPERFORMANCEFUELECONOMYIMPROVEMENTSCANBEMEASUREDVIATHEUSEPA55/45DRIVINGCYCLES1AUTOMOTIVEMANUFACTURERSUSETHISTESTTOCERTIFYAVEHICLESFUELECONOMYTHISTESTCANALSOBEUSEDTOSHOWFUELECONOMYIMPROVEMENTSINGEAROILLUBRICANTSMANYMANUFACTURERSFEELTHATSTABILIZEDOPERATINGTEMPERATUREUNDERTHEPROPERCONTROLLEDCONDITIONSISANIMPORTANTINDICATOROFTHEDURABILITYPERFORMANCEOFALUBRICANTUNDERSEVERECONDITIONSINTHECASEOFOPERATINGTEMPERATUREASSESSMENT,THEREEXISTSNOSTANDARDTESTMETHODORMETHODOLOGYTYPICALLY,WHENAPPLIEDINALABORATORYTESTSTANDASINGLEAXLEISBROKENINANDTHENUSEDREPEATEDLYTOEVALUATEMANYLUBRICANTSUNDERSEVERECONDITIONS,THESTABILIZEDOPERATINGTEMPERATURESFORAGIVENREFERENCEOILDECREASESEACHTIMEITISRUNINANAXLEASTHENUMBEROFTESTRUNSONANAXLEINCREASESTHESTABILIZEDOPERATINGTEMPERATUREOFTHEREFERENCEOILISLOWERTHISPOSESAPROBLEMWHENEVALUATINGCANDIDATELUBRICANTSWITHACHANGINGTARGET,HOWCANALUBRICANTBEACCURATELYEVALUATEDTHISPAPERDESCRIBESALABORATORYTESTMETHODTHATACCOUNTSFORTESTTOTESTCHANGESIN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