Navistar ProStar+ User Manual

Operation
Undernormalhighwayconditions(goodtraction),thePDL
shouldbedisengaged,whichallowsdifferentialactionbetween
theforwardrearaxleandthebackrearaxlepreventinginter-axle
differentialwearduetosuchthingsasunequallywornor
mismatchedtires.
DriverControlledDifferentialLock
TheDifferentialLockfeaturelockstogethertheaxle's
leftandrightaxleshaftsforimprovedtractionon
reducedtractionsurfaces.
Somevehiclesareequippedwiththisoptionaldriver
controlleddifferentiallockfeature(DIFFLOCK).The
airactuatedtractiondevicecanbemanuallyshifted
fromthevehiclecab.Byactuatingaswitch,mounted
ontheinstrumentpanel,thedrivercanlockorunlocktherear
axledifferential(s)whenthevehicleismovingorstopped.
Othervehicleswithtandemrearaxles
(6X4)areequippedwithtwooptional
driver-controlleddifferentiallockfeatures
(DIFFFRAXLE/LOCKandDIFFRRAXLE
/LOCK).Theairactuatedtractiondevices
canbemanuallyshiftedfromthevehicle
cab.Byactuatingtheswitches,mounted
ontheinstrumentpanel,thedrivercanindependentlylockor
unlocktheforward-rearand/orrear-rearaxledifferentialswhen
thevehicleismovingorstopped.
Whenthedifferentialisfullylocked,thevehiclewillhaveaslight
“under-steer”condition.Thiswillincreasetheturningradiusof
thevehicle.
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.
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Navistar ProStar+ Specifications

General

Brand	Navistar
Model	ProStar+
Category	Trucks
Language	English