CDL COMBINATION VEHICLES
ENDORSEMENT ACTUAL TEST PAPER 2026
UPDATED QUESTIONS ANSWERS REVIEW
● Which statement best illustrates the "crack-the-whip" effect?. Answer:
Your trailer is half full, and the cargo is loaded in the front of the trailer.
When
When you make a quick lane change or sudden movement of your
steering wheel, the rear trailer tends to swing out. The force of the rear
trailer becomes amplified, causing it to roll over.
● On a double or triple vehicle, which wheels offtrack the most?.
Answer: The rear wheels of the last trailer
● After coupling, make sure that the air lines are not crossed. How
should you do this?. Answer: Adjust the air supply knob to send air to
the trailer brakes. Turn off the engine once the air pressure normalizes.
Then listen for the sound of escaping air as the brakes are released.
● If your vehicle gets stuck on a railroad track, you should. Answer: get
away from your vehicle and call 911 or the posted emergency number.
● To drive a triple combination vehicle, you must have. Answer: a Class
A CDL with a doubles/triples (T) endorsement.
, ● During uncoupling, you should disconnect the electrical cable and.
Answer: hang it with the plug down.
● What is the safest way for you to make a turn without entering
another traffic lane?. Answer: You should turn wide as you complete the
turn.
● Even before antilock braking systems (ABS) were required, some
vehicles already had them. How can you check if your vehicle has
ABS?. Answer: Look under the vehicle for the ECU and wheel speed
sensor wires coming from the back of the brakes.
● If your test of the tractor protection valve is successful,. Answer: the
tractor protection valve control (trailer air supply control) will pop out or
go from "normal" to "emergency."
● When you're pulling doubles or triples, the shut-off valves should
always be. Answer: open except for those on the last trailer.
● You can confirm that air is going to all brakes in your trailers by.
Answer: opening the emergency line shut-off valve and then the service
line valve at the rear of the last trailer and listening for air escaping each
time.
ENDORSEMENT ACTUAL TEST PAPER 2026
UPDATED QUESTIONS ANSWERS REVIEW
● Which statement best illustrates the "crack-the-whip" effect?. Answer:
Your trailer is half full, and the cargo is loaded in the front of the trailer.
When
When you make a quick lane change or sudden movement of your
steering wheel, the rear trailer tends to swing out. The force of the rear
trailer becomes amplified, causing it to roll over.
● On a double or triple vehicle, which wheels offtrack the most?.
Answer: The rear wheels of the last trailer
● After coupling, make sure that the air lines are not crossed. How
should you do this?. Answer: Adjust the air supply knob to send air to
the trailer brakes. Turn off the engine once the air pressure normalizes.
Then listen for the sound of escaping air as the brakes are released.
● If your vehicle gets stuck on a railroad track, you should. Answer: get
away from your vehicle and call 911 or the posted emergency number.
● To drive a triple combination vehicle, you must have. Answer: a Class
A CDL with a doubles/triples (T) endorsement.
, ● During uncoupling, you should disconnect the electrical cable and.
Answer: hang it with the plug down.
● What is the safest way for you to make a turn without entering
another traffic lane?. Answer: You should turn wide as you complete the
turn.
● Even before antilock braking systems (ABS) were required, some
vehicles already had them. How can you check if your vehicle has
ABS?. Answer: Look under the vehicle for the ECU and wheel speed
sensor wires coming from the back of the brakes.
● If your test of the tractor protection valve is successful,. Answer: the
tractor protection valve control (trailer air supply control) will pop out or
go from "normal" to "emergency."
● When you're pulling doubles or triples, the shut-off valves should
always be. Answer: open except for those on the last trailer.
● You can confirm that air is going to all brakes in your trailers by.
Answer: opening the emergency line shut-off valve and then the service
line valve at the rear of the last trailer and listening for air escaping each
time.
