NOTE:Thetransmissionretarderisconguredaseitheralow,
medium,orhighcapacityretarderbyTCMcalibration.Allison
TransmissionrequireswrittenvehicleOEMapprovalbeforeaservice
outletincreasestheretardercapacityatacustomer'srequest.
Existingvehicledrivelines,differentials,axles,andthecoolingsystem
mustbedesignedfortheadditionalretardertorquegeneratedifa
highercapacityretardercalibrationisinstalled.Thecosttomodify
retardercapacityistheresponsibilityofthecustomer.
TheamountofRetarderModulationRequest(RMR)iscontrolledbythe
operatoranddependsonthetypeofretardercontrolusedinthevehicle.
Varioushand,footandautomaticcontroltechniquesareused.Referto
Table4–7.BeginningwithAllison5thGenerationControls,theTCMalso
activatesorlimitsretarderoperationinresponsetotorquespeedcontrolor
electronicretardercontrolmessagesreceivedonthevehicle’sSAEJ1939
Datalink.ContactyourOEMtounderstandhowtheretardercontrolshave
beenintegratedintoyourvehicle.
ThepresenceofaretardermustbeautodetectedbeginningwithAllison5th
GenerationControls.
NOTE:Theretarderenableswitchisusedtoturntheretarderofffor
slipperyroadconditions.
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