Peterbilt 348 2017 - Descending a Grade; Engine Overspeed

DRIVINGTIPSANDTECHNIQUES
DescendingaGrade
WARNING!
Donotholdthebrakepedaldown
toolongortoooftenwhilegoing
downasteeporlonggrade.This
couldcausethebrakestooverheat
andreducetheireffectiveness.Asa
result,thevehiclewillnotslowdown
attheusualrate.T oreducetherisk
ofanaccidentwhichcouldcause
deathorpersonalinjury,beforego-
ingdownasteeporlonggrade,re-
ducespeedandshiftthetransmis-
sionintoalowergeartohelpcontrol
yourvehiclespeed.Failuretofollow
proceduresforproperdownhilloper-
ationcouldresultinlossofvehicle
control.
EngineOverspeed
CAUTION
Toavoidenginedamage,donotlet
theenginerpmgobeyondthemaxi-
mumgovernedrpm—valvedamage
couldresultifoverspeedconditions
occur.
NOTE
Oftentheserecommendationsare
secondarytomaintaininganade-
quateandsafespeedrelativetothe
surroundingtrafcandroadcondi-
tions.
Operatetheenginewithintheoptimum
enginerpmrangeanddonotallow
therpm'stoexceedthemaximum
governedspeed.SeeyourEngine
OperationandMaintenancemanual
forinformationregardingenginerpm.
Whentheengineisusedasabrake
tocontrolvehiclespeed(e.g.,while
drivingdownagrade),donotallow
theenginerpmtoexceedmaximum
governedspeed.
Undernormalloadandroadconditions
operatetheengineinthelowerendof
therange.
(03/17)Y53-6060-1C14-63
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