Operation
lockorunlocktheforward-rearand/orrear-rearaxledifferentials
whenthevehicleismovingorstopped.
Whenthedifferentialisfullylocked,thevehiclewillhaveaslight
under-steercondition.Thiswillincreasetheturningradiusofthe
vehicle.
Onvehicleswithmultipledriveaxles,thedifferentiallockcanbe
usedinconjunctionwiththePowerDividerLock(PDL)toachieve
maximumavailabletractioninadverseroadsurfaceconditions.
Tolimitstressontheaxleandtiresduringvehicleturning
maneuversandimprovestability,theuseofthedifferentiallock
mustbelimitedtolowvehiclespeeds,under25mph(40km/h).
Also,tomaintainvehiclestability,thedifferentialmustnotbe
lockedwhenthevehicleistravelingdownsteepgradesand
tractionisminimal.DIFFLOCKwillautomaticallydisengage
whenvehiclespeedsexceedapproximately25mph(40km/h).
Donotengagethelockingdifferentialwhenthetiresare
spinning.
Thevehiclemayneedtobedeceleratedorturnedonceortwice
forthedifferentiallocktofullydisengage.
RearSuspension
RearAirRideSuspension
CAUTION
Topreventridedegradationandsuspension
damage,thevehiclemustnotbeoperatedonthe
roadwithoutairinthesuspensionairbags.
RearAirRideSuspensionsautomaticallyadjusttodifferentloads
tomaintainconstantframeheight.Thesystemmaintainsvehicle
ridequalityanddrivercomfort.
RearAirSuspensionAirDump
Thisfeaturealsoallowstherearofthevehicletolowerseveral
inchesfortrailerattachment/detachment.
Thesystemiscontrolledbythetwo-position
SUSPDUMPswitchwithanindicatorlight
intheSUSPDUMPposition.Thisswitch
controlssolenoids,whichdirectairtothe
suspensiondumpandheightvalve.
WhentheSUSPDUMPswitchisintheSUSP
DUMPpositionandthevehiclespeedisbelow
5mph(8km/h),airsuppliedtotherearair
suspensionisreleased,loweringtheframeforloading.
Placingtheswitchinthetruckiconpositioncausesairtollor
remainintheairsuspensionforproperoperatingrideheight.
TheSUSPDUMPswitchwilloperatetheIROSsystemonlyifthe
ignitionswitchisineitherACCorONpositionandtheairtanks
havesufcientpressuretollthesuspension.Whentheignition
switchisturnedOFF,powertothesolenoidwillberemoved;
therefore,thesuspensionwillremaininthestatelastsetbythe
SUSP/DUMPswitch.
NOTE:Thesuspensionwilldumpwhentheignitionswitch
isineithertheACCorONposition,butwillllonlywhen
theignitionswitchisintheONposition.
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