Navistar International LT Series - Driver-Controlled Differential Lock

Operation
CAUTION
Topreventvehicleand/orcomponentdamage,
engagethePDLonlywhenstoppedormovingat
lowspeed.NevertrytoengagethePDLwhilethe
wheelsarespinningasthismayresultinshock
damagetothepowerdividercomponents.
Whenencounteringslipperyhighwayconditions(poortraction),
thePDLcanbeengagedatalow,evenspeed.Momentarily
lettingofftheacceleratorwillengagethedifferentiallock.A
warningindicatorontheinstrumentpanelindicateswhenthe
inter-axledifferentialislocked.
Whenhighwayconditionsimprove(goodtraction),thePDL
shouldbedisengaged,againatalow,evenspeed.Letting
upontheacceleratormomentarilywillunlocktheinter-axle
differential.
Tandemaxlepowerdividersorinter-axle
differentialsintheforwardrearaxleare
controlledbytheinstrumentpanelmounted
PowerDividerLock(PDLLOCK)switch.
Theswitchindicatorwillturnonwhenthe
PDLisengaged(locked).Thevehiclemay
beelectronicallyprogrammedtoprovidean
alarmwhenaspeedisreachedwhereitisnot
appropriatetohavethepowerdividerlocked.Inthisevent,an
alarmwillsound(5beeps)andtheswitchindicatorwillash
slowly(oncepersecond).Afastashing(twicepersecond)
switchindicatorsigniesaprobleminthePDLsystem.
Undernormalhighwayconditions(goodtraction),thePDL
shouldbedisengaged,whichallowsdifferentialactionbetween
theforwardrearaxleandthebackrearaxle,preventing
inter-axledifferentialwearduetosuchthingsasunequallyworn
ormismatchedtires.
Driver-ControlledDifferentialLock
TheDifferentialLockfeaturelockstogetherthe
axle'sleftandrightaxleshaftsforimproved
tractiononreducedtractionsurfaces.
Somevehiclesareequippedwiththisoptional
driver-controlleddifferentiallockfeature(DIFF
LOCK).Theairactuatedtractiondevicecan
bemanuallyshiftedfromthevehiclecab.By
actuatingaswitch,mountedontheinstrument
panel,thedrivercanlockorunlocktherearaxledifferential(s)
whenthevehicleismovingorstopped.
Othervehicleswithtandem
rearaxles(6x4)are
equippedwithtwooptional
driver-controlleddifferential
lockfeatures(DIFFLOCK
1andDIFFLOCK2).The
airactuatedtractiondevices
canbemanuallyshifted
fromthevehiclecab.By
actuatingtheswitches,
mountedontheinstrumentpanel,thedrivercanindependently
174