Operation
Tractor-TrailerConnections
WARNING
Topreventpropertydamage,personalinjury,
and/ordeath,wheneverpossible,maketrailer
connectionswhilestandingontheground.
Provideadequatelightingofworkingareas.
Inclementweatherandaccumulatedroad
contaminationdepositsonhandholdsand
steppingsurfacesrequireextracaretoprevent
slipsandfalls.
WARNING
Topreventpersonalinjuryand/ordeath,donot
climbonthebackofatractorunlessithasbeen
providedwithadeckplateandhandholds.Use
athree-pointstancewhenclimbingupanddown
fromadeckplate.Donotjumpfromvehicle.
Connecting/DisconnectingaTrailertoaVehiclewithAir
Suspension
TheAirSuspensionhasadumpvalvesystemoption(Code
14899)thatpermitsexhaustingairfromthesuspensionsystem,
thusloweringtheframewhenconnecting,disconnecting,or
loadingthetrailer.Thevehiclespeedmustbebelow5mph(8
km/h)beforetheswitchwilloperatethevalve.
Whenconnectingtoatrailer,switchtheSUSP/DUMPswitch,
locatedontheinstrumentpanel,totheDUMPposition,andair
willexhaustfromthesuspensionsystemloweringthetractor.
Thiswillpermitbackingunderthetrailerwithoutundueloading
ofsuspensionsystem.Aftermakingtheconnectiontothetrailer,
returntheswitchtotheSUSPposition,thenraiselandinggear.
Whendisconnectingthetrailer,lowerthelandinggear,
disconnectthebrakehosesandrearlightconnectorsfromthe
trailer,andpullthereleaseleveronthefthwheel.Slowlypull
thetractorforwardjustfarenoughtoreleasethekingpinfrom
thefthwheelandstop.SwitchtheSUSP/DUMPswitchtothe
DUMPpositionandpullthetractorawayfromthetrailer.
TheSUSP/DUMPswitchmustbereturnedtothedownSUSP
positionbeforeoperatingwithatraileroroperatinginthebobtail
mode.
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