CDL Combination Vehicle Test 2 Questions And
Answers With Complete Solutions 2026.
1. You have coupled with a semi trailer. In what position should you put
the front
trailer supports (landing gear) before driving away?
A. Fully lowered with the crank handle secured in its bracket.
B. Fully raised with the crank handle secured in its bracket
C. Raised about half way with the crank handle removed. - ANSWER: B.
Fully raised with the crank handle secured in its bracket
2. Air lines on a combination vehicle are often colored to keep them
from getting
mixed up. The emergency line is _____, and the service line is _____
A. Red, blue
B. Blue, red
C. Red, black - ANSWER: A. Red, blue
3. Which of these statements is true?
A. Light vehicles need more braking power to stop than heavy ones.
B. Because of brake lag you should always delay braking until you have
no other
choice.
C. "Bobtail" tractors can take longer to stop than a fully loaded
combination
, vehicle. - ANSWER: C. "Bobtail" tractors can take longer to stop than a
fully loaded combination
vehicle.
4. You are coupling a tractor and semi trailer and have connected the
air lines.
Before backing under the trailer, you should:
A. Make sure that the trailer brakes are off
B. Supply air to the trailer system, then pull out the trailer air supply
knob to lock the trailer brakes
C. Make sure the landing gear is fully raised - ANSWER: B. Supply air to
the trailer system, then pull out the trailer air supply knob to lock the
trailer brakes
The trailer hand valve should be used:
A. Only to test the trailer service brakes
B. To prevent a trailer jackknife.
C. To avoid over heating the tractor service brakes. - ANSWER: A. Only
to test the trailer service brakes
The air leakage rate for a combination vehicle (engine off, brakes off)
should be
no more than _____ psi per minute.
A. 2
B. 3
C. 4 - ANSWER: B. 3
Answers With Complete Solutions 2026.
1. You have coupled with a semi trailer. In what position should you put
the front
trailer supports (landing gear) before driving away?
A. Fully lowered with the crank handle secured in its bracket.
B. Fully raised with the crank handle secured in its bracket
C. Raised about half way with the crank handle removed. - ANSWER: B.
Fully raised with the crank handle secured in its bracket
2. Air lines on a combination vehicle are often colored to keep them
from getting
mixed up. The emergency line is _____, and the service line is _____
A. Red, blue
B. Blue, red
C. Red, black - ANSWER: A. Red, blue
3. Which of these statements is true?
A. Light vehicles need more braking power to stop than heavy ones.
B. Because of brake lag you should always delay braking until you have
no other
choice.
C. "Bobtail" tractors can take longer to stop than a fully loaded
combination
, vehicle. - ANSWER: C. "Bobtail" tractors can take longer to stop than a
fully loaded combination
vehicle.
4. You are coupling a tractor and semi trailer and have connected the
air lines.
Before backing under the trailer, you should:
A. Make sure that the trailer brakes are off
B. Supply air to the trailer system, then pull out the trailer air supply
knob to lock the trailer brakes
C. Make sure the landing gear is fully raised - ANSWER: B. Supply air to
the trailer system, then pull out the trailer air supply knob to lock the
trailer brakes
The trailer hand valve should be used:
A. Only to test the trailer service brakes
B. To prevent a trailer jackknife.
C. To avoid over heating the tractor service brakes. - ANSWER: A. Only
to test the trailer service brakes
The air leakage rate for a combination vehicle (engine off, brakes off)
should be
no more than _____ psi per minute.
A. 2
B. 3
C. 4 - ANSWER: B. 3
