CDL - COMBINATION VEHICLE PRACTICE
TEST 2025 QUESTIONS & ANSWERS
The trailer hand valve works the trailer brakes. Which of these statements is
true?
1. the foot brake sends air to all the brakes on the vehicle (including the
trailer(s))
2. The trailer hand valve should be used only to test the trailer brakes
3. all the above - correct-answer-all the above
Where should the tractor be when you inspect the landing gear after uncoupling
the trailer?
1. With the fifth wheel directly beneath the kingpin
2. completely cleared from the trailer
3. with the tractor frame under the trailer - correct-answer-with the tractor
frame under the trailer
After you lock the kingpin into the fifth wheel, you should check the connection
by pulling
1. the tractor ahead gently with the trailer brakes locked
2. forward 50 feet, then turning right, and then left
3. the tractor ahead sharply to release the trailer brakes - correct-answer-
, the tractor ahead gently with the trailer brakes locked
At night, when a vehicle is carrying a load that extends four feet or more
beyond the rear of the body, there must be at the extreme end of the
load.
1. red lights
2. red flags
3. a red flag - correct-answer-red lights
Which type of truck-trailer combination has the greatest chance of a "crack-the-
whip" rollover?
1. A tractor pulling three trailers
2. A single tractor trailer
3. A tractor pulling two trailers - correct-answer-A tractor pulling 3 trailers
Air and electrical lines from the tractor to the trailer should be...
1. pulled tight with very little slack
2. secured but with enough slack for turns
3. resting on the frame of the tractor. - correct-answer-secured but with
enough slack for turns
Compared with a straight truck or bus, there are things to
TEST 2025 QUESTIONS & ANSWERS
The trailer hand valve works the trailer brakes. Which of these statements is
true?
1. the foot brake sends air to all the brakes on the vehicle (including the
trailer(s))
2. The trailer hand valve should be used only to test the trailer brakes
3. all the above - correct-answer-all the above
Where should the tractor be when you inspect the landing gear after uncoupling
the trailer?
1. With the fifth wheel directly beneath the kingpin
2. completely cleared from the trailer
3. with the tractor frame under the trailer - correct-answer-with the tractor
frame under the trailer
After you lock the kingpin into the fifth wheel, you should check the connection
by pulling
1. the tractor ahead gently with the trailer brakes locked
2. forward 50 feet, then turning right, and then left
3. the tractor ahead sharply to release the trailer brakes - correct-answer-
, the tractor ahead gently with the trailer brakes locked
At night, when a vehicle is carrying a load that extends four feet or more
beyond the rear of the body, there must be at the extreme end of the
load.
1. red lights
2. red flags
3. a red flag - correct-answer-red lights
Which type of truck-trailer combination has the greatest chance of a "crack-the-
whip" rollover?
1. A tractor pulling three trailers
2. A single tractor trailer
3. A tractor pulling two trailers - correct-answer-A tractor pulling 3 trailers
Air and electrical lines from the tractor to the trailer should be...
1. pulled tight with very little slack
2. secured but with enough slack for turns
3. resting on the frame of the tractor. - correct-answer-secured but with
enough slack for turns
Compared with a straight truck or bus, there are things to
