Allison Transmission T 280

Table4–1.DESCRIPTIONOFAVAILABLERANGES(cont'd)
DescriptionofAvailableRanges(refertoFigure4–1)
WARNING:D(Drive)maynotbeattainedduetoanactive
inhibitor.AlwaysapplytheservicebrakeswhenselectingD
(Drive)topreventunexpectedvehiclemovementandbecause
aserviceinhibitmaybepresent.Whentheselectedrangeis
ashing,itindicatestheshifttoD(Drive)isinhibited.Determine
ifdiagnosticcodesareactiveifD(Drive)isnotattained.Refer
to7.5SELECTORDISPLAYDESCRIPTIONSFORACTIVE
DIAGNOSTICTROUBLECODES(DTCs)ANDINHIBITS.
CAUTION:DonotidleinD(Drive)formorethanve
minutes.ExtendedidlinginD(Drive)maycausetransmission
overheatinganddamage.AlwaysselectN(Neutral)iftimeat
idleexceedsveminutes.
NOTE:IfequippedwithaHIGHIDLEswitch,turntheHIGH
IDLEswitchoffbeforeshiftingfromN(Neutral)toD(Drive)
orR(Reverse).D(Drive)orR(Reverse)maynotbeattained
unlesstheshiftismadewiththeengineatidle.Also,beaware
ofotherinterlocksthatwouldpreventattainingD(Drive)or
R(Reverse).Example:“servicebrakesnotapplied”(service
brakeinterlockpresent).
DThetransmissioninitiallyattainsitslowestprogrammedrange
whenD(Drive)isselected.Asvehiclespeedincreases,
thetransmissionupshiftsautomaticallythrougheachrange.
Asthevehicleorequipmentslowsdown,thetransmission
automaticallydownshiftstothecorrectrange.Thekeypadpush
buttonandbump-shiftleverdisplayshowsthehighestrange
availableinD(Drive).Thestrippushbuttonilluminatesthe
upperrightcorneroftheDbuttonwhenpushed.
D(Primary
(ROAD)Mode
OFSModels)
Thetransmissioninitiallyattainsitslowestprogrammedrange
whenD(Drive)isselected.Asvehiclespeedincreases,
thetransmissionupshiftsautomaticallythrougheachrange.
Asthevehicleorequipmentslowsdown,thetransmission
automaticallydownshiftstothecorrectrange.Thekeypadpush
buttonandbump-shiftleverdisplayshowsthehighestrange
availableinD(Drive).Thestrippushbuttonilluminatesthe
upperrightcorneroftheDbuttonwhenpushed.
D(Secondary
(RIG)ModeOFS
Models)
Goestotherangesetinthecalibrationsetforstationarymode.
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