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CDL COMBINATION VEHICLES Actual 2025 Exam with
Questions and Answers () 100%
Guarantee Pass
How should you test the tractor semi trailer combination for being properly
coupled? - ..(ANSWER)...Pull gently forward in low gear against the locked trailer
brakes, then inspect your coupling.
When coupling to the trailer, how far do you back up before stopping the first
time? - ..(ANSWER)...Until the fifth wheel plate just touches the trailer.
What do you check before backing under the trailer? - ..(ANSWER)...Make sure
the trailer brakes are set.
Air lines on a combination vehicle are often colored to keep them from getting
mixed up. What color is the emergency line and what color is the service line? -
..(ANSWER)...Red and blue.
After you back up to the trailer and the fifth wheel plate touches the trailer, you
set the tractor park brake, get out and hook up the emergency and service air
lines. Then what do you do before backing under the trailer? -
..(ANSWER)...Supply air to the trailer system, then pull out the trailer air supply
knob to fully set the trailer brakes.
What three things can you do to prevent rollovers? - ..(ANSWER)...Keep your load
centered, keep the load as low in the trailer as possible, and go slow around
turns.
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How far do you raise the landing gear on your trailer? - ..(ANSWER)...Crank it up
as far as it will go.
You have coupled with a semi trailer. In what position should you put the landing
gear before driving away? - ..(ANSWER)...Fully raised with the crank handle
secured in its bracket.
When uncoupling, what could happen if you park the trailer at an angle? -
..(ANSWER)...You could do damage to the landing gear and dolly legs.
Why should you lock the tractor glad hands together or couple them to the
dummy glad hands when bobtailing? - ..(ANSWER)...It will keep dirt and water out
of the lines.
When backing under a trailer, you should expect the trailer to be lifted slightly by
the fifth wheel plate. - ..(ANSWER)...True.
Before you begin coupling, you should check your travel path for obstacles and
hazards. - ..(ANSWER)...True.
What should your air supply pressure gauge read before backing under a trailer? -
..(ANSWER)...100 - 125 psi.
CDL COMBINATION VEHICLES Actual 2025 Exam with
Questions and Answers () 100%
Guarantee Pass
How should you test the tractor semi trailer combination for being properly
coupled? - ..(ANSWER)...Pull gently forward in low gear against the locked trailer
brakes, then inspect your coupling.
When coupling to the trailer, how far do you back up before stopping the first
time? - ..(ANSWER)...Until the fifth wheel plate just touches the trailer.
What do you check before backing under the trailer? - ..(ANSWER)...Make sure
the trailer brakes are set.
Air lines on a combination vehicle are often colored to keep them from getting
mixed up. What color is the emergency line and what color is the service line? -
..(ANSWER)...Red and blue.
After you back up to the trailer and the fifth wheel plate touches the trailer, you
set the tractor park brake, get out and hook up the emergency and service air
lines. Then what do you do before backing under the trailer? -
..(ANSWER)...Supply air to the trailer system, then pull out the trailer air supply
knob to fully set the trailer brakes.
What three things can you do to prevent rollovers? - ..(ANSWER)...Keep your load
centered, keep the load as low in the trailer as possible, and go slow around
turns.
, 2|Page
How far do you raise the landing gear on your trailer? - ..(ANSWER)...Crank it up
as far as it will go.
You have coupled with a semi trailer. In what position should you put the landing
gear before driving away? - ..(ANSWER)...Fully raised with the crank handle
secured in its bracket.
When uncoupling, what could happen if you park the trailer at an angle? -
..(ANSWER)...You could do damage to the landing gear and dolly legs.
Why should you lock the tractor glad hands together or couple them to the
dummy glad hands when bobtailing? - ..(ANSWER)...It will keep dirt and water out
of the lines.
When backing under a trailer, you should expect the trailer to be lifted slightly by
the fifth wheel plate. - ..(ANSWER)...True.
Before you begin coupling, you should check your travel path for obstacles and
hazards. - ..(ANSWER)...True.
What should your air supply pressure gauge read before backing under a trailer? -
..(ANSWER)...100 - 125 psi.
