COMBINATION VEHICLES 4: CDL QUESTIONS
WITH CORRECT ANSWERS 2025
InMnormalMdriving,MsomeMdriversMuseMtheMhandMvalveMbeforeMapplyingMtheMbrakeMpedalMtoMprev
entMaMjackknife.MWhichMofMtheseMstatementsMisMtrue?
1.MItMshouldMnotMbeMdone
2.MItMresultsMinMlessMskiddingMthanMusingMtheMbrakeMpedalMalone
3.MItMisMtheMbestMwayMtoMbrakeMandMkeepMtheMtruckMinMaMstraightMlineM-MCORRECTMANSWER-
CORRECTMANSWER:
1.MItMshouldMnotMbeMdone
EXPLANATION:
TheMtrailerMhandMvalve,MalsoMcalledMtheMtrolleyMvalveMorMJohnsonMbar,MworksMtheMtrailerMbrakes.M
TheMtrailerMhandMvalveMshouldMbeMusedMonlyMtoMtestMtheMtrailerMbrakes.MDoMnotMuseMitMinMdrivin
gMbecauseMofMtheMdangerMofMmakingMtheMtrailerMskid.
YouMshouldMnotMbackMaMtractorMunderMaMtrailerMuntilMtheMwholeMairMsystemMis:
1.MAtMnormalMpressure
2.MHalfMtheMmaximumMpressure
3.MBetweenM60MandM80MPSIM-MCORRECTMANSWER-CORRECTMANSWER:
1.MAtMnormalMpressure
, EXPLANATION:
MakeMsureMairMpressureMisMupMtoMnormal.
AfterMyouMsupplyMairMtoMtheMtrailer,MmakeMsureMtheMairlinesMareMnotMcrossedMandMtheMtrailerMbra
kesMareMworking.MThisMcanMbeMdoneMby:
1.MTurningMonMtheMparkingMbrakesMfromMtheMcab
2.MApplyingMandMreleasingMtheMtrailerMbrakesMandMlisteningMforMbrakeMsounds
3.MLiftingMtheMbrakeMpedalM-MCORRECTMANSWER-CORRECTMANSWER:
2.MApplyingMandMreleasingMtheMtrailerMbrakesMandMlisteningMforMbrakeMsounds
EXPLANATION:
WaitMuntilMtheMairMpressureMisMnormal,MthenMshutMengineMoffMsoMyouMcanMhearMtheMbrakes.MChec
kMbrakeMsystemMforMcrossedMair-
linesMby:MapplyingMandMreleasingMtrailerMbrakesMandMlistenMforMsoundMofMtrailerMbrakesMbeingMap
pliedMandMreleased.MYouMshouldMhearMtheMbrakesMmoveMwhenMappliedMandMairMescapeMwhenMth
eMbrakesMareMreleased.
WhatMisMtheMsafestMwayMforMyouMtoMmakeMaMturnMwithoutMenteringManotherMtrafficMlane?
1.MIfMyouMmustMcrossMintoMtheMoncomingMlaneMtoMmakeMaMturnMandMyouMseeMvehiclesMcomingMto
wardMyou,MstopMandMbackMupMforMthem.
2.MYouMshouldMturnMwideMasMyouMcompleteMtheMturn.
WITH CORRECT ANSWERS 2025
InMnormalMdriving,MsomeMdriversMuseMtheMhandMvalveMbeforeMapplyingMtheMbrakeMpedalMtoMprev
entMaMjackknife.MWhichMofMtheseMstatementsMisMtrue?
1.MItMshouldMnotMbeMdone
2.MItMresultsMinMlessMskiddingMthanMusingMtheMbrakeMpedalMalone
3.MItMisMtheMbestMwayMtoMbrakeMandMkeepMtheMtruckMinMaMstraightMlineM-MCORRECTMANSWER-
CORRECTMANSWER:
1.MItMshouldMnotMbeMdone
EXPLANATION:
TheMtrailerMhandMvalve,MalsoMcalledMtheMtrolleyMvalveMorMJohnsonMbar,MworksMtheMtrailerMbrakes.M
TheMtrailerMhandMvalveMshouldMbeMusedMonlyMtoMtestMtheMtrailerMbrakes.MDoMnotMuseMitMinMdrivin
gMbecauseMofMtheMdangerMofMmakingMtheMtrailerMskid.
YouMshouldMnotMbackMaMtractorMunderMaMtrailerMuntilMtheMwholeMairMsystemMis:
1.MAtMnormalMpressure
2.MHalfMtheMmaximumMpressure
3.MBetweenM60MandM80MPSIM-MCORRECTMANSWER-CORRECTMANSWER:
1.MAtMnormalMpressure
, EXPLANATION:
MakeMsureMairMpressureMisMupMtoMnormal.
AfterMyouMsupplyMairMtoMtheMtrailer,MmakeMsureMtheMairlinesMareMnotMcrossedMandMtheMtrailerMbra
kesMareMworking.MThisMcanMbeMdoneMby:
1.MTurningMonMtheMparkingMbrakesMfromMtheMcab
2.MApplyingMandMreleasingMtheMtrailerMbrakesMandMlisteningMforMbrakeMsounds
3.MLiftingMtheMbrakeMpedalM-MCORRECTMANSWER-CORRECTMANSWER:
2.MApplyingMandMreleasingMtheMtrailerMbrakesMandMlisteningMforMbrakeMsounds
EXPLANATION:
WaitMuntilMtheMairMpressureMisMnormal,MthenMshutMengineMoffMsoMyouMcanMhearMtheMbrakes.MChec
kMbrakeMsystemMforMcrossedMair-
linesMby:MapplyingMandMreleasingMtrailerMbrakesMandMlistenMforMsoundMofMtrailerMbrakesMbeingMap
pliedMandMreleased.MYouMshouldMhearMtheMbrakesMmoveMwhenMappliedMandMairMescapeMwhenMth
eMbrakesMareMreleased.
WhatMisMtheMsafestMwayMforMyouMtoMmakeMaMturnMwithoutMenteringManotherMtrafficMlane?
1.MIfMyouMmustMcrossMintoMtheMoncomingMlaneMtoMmakeMaMturnMandMyouMseeMvehiclesMcomingMto
wardMyou,MstopMandMbackMupMforMthem.
2.MYouMshouldMturnMwideMasMyouMcompleteMtheMturn.