CDL Double-Triple
Trailers Test

This is the Commercial Vehicle Driver's License Test covering Double and Triple Trailers. You will be presented with 40 questions and you must answer 34 questions correctly to pass. There is no time limit. You may not go back once you answer a question. Click the "Start Quiz" button below to begin. Good luck!

1 / 40

For emergency braking to avoid a crash when driving a double trailer you should:

none of the answers listed

slam down the brake pedal and keep pressure on it

use the trailer brakes only

do stab or controlled braking

2 / 40

What is the best way to stop all skids?

quickly turn the steering wheel side to side

restore traction back to the tires

use controlled or stab braking

accelerate and countersteer

3 / 40

Why should you test the tractor protection valve?

to avoid the emergency brakes kicking on due to loss of air

to avoid loss of air from the trailer brakes

all answers listed

to avoid loss of air from the air hose

4 / 40

What is most likely to occur when driving a set of doubles and a set of trailer wheels goes into a skid?

nothing will occur

there will be a trailer jackknife

the rig will slide sideways but stay in a straight line

no matter how you turn the steering wheel, the rig will continue in a straight line

5 / 40

In what position should shut off valves on the rear of the last trailer be in on a set of double trailers?

in a open position

in a closed position

in a open position for the rear trailer and a closed position for the front trailer

in a closed position for the rear trailer and open position for the front trailers

6 / 40

The best way to have control on curves is:

to shift to a lower gear before entering the curve

keep pressure on the brake pedal through the turn

you do not need to do anything different

to decrease to your safe speed before entering the curve and then accelerate through it

7 / 40

In what position should the converter dolly air tank drain valve be in for double trailer combination?

in an open position

in a 1/3 open position

in a closed position

in a halfway closed position

8 / 40

What do you need to do to supply air to the air tranks of the second trailer?

open up the shutt off valves on the rear of the first trailer and close the shut off valve at the back of the second trailer

none of the answers listed

close the shut off valves at the back of each trailer

open the shut off valve at the back of both trailers

9 / 40

Select the true statement in regards to quick steering movements and double trailers:

it is easier to tip doubles and triples from quick steering movements than other vehicles

you should apply a firm pressure to the brake pedal at the same moment you do quick steering movements

it is easier to countersteer doubles/triples than other vehicles

nothing will occur

10 / 40

The trailer height is correct for connecting a converter dolly to a second or third trailer when:

the kingpin is over the fifth wheel

the trailer will rise slightly when the converter dolly is backed underneath it

all answers listed

the center of the kingpin is past the locking jaw

11 / 40

In what position should the converter dolly air tank drain valves and pintle hook be in?

closed and open

open and latched

closed and latched

open and open

12 / 40

Select the true statement about double or triple trailers.

they present a rearward amplification hazard

all answers listed

they can roll over duee to abrupt steering movements

they can have a dangerous "crack the whip" effect

13 / 40

Select the true statement in regards to converter dollies:

they typically have a lot of stopping power because of their size

they typically have small braking power because of their size

they typically do not have spring brakes

they typically require a hand converter

14 / 40

Select the action that is not appropriate when driving on slippery roads:

use a light pressure on the brake and accelerator pedals

avoid having traffic in your side space

use a speed retarder or engine brake

none of the answers listed

15 / 40

How should you inspect a converter dolly?

as if it is an engine

as if it is cargo

as if it is an axle with a fifth wheel

as if it is a trailer

16 / 40

How do you make sure the trailer height is correct before coupling?

visually check that they are level height wise

visually check that the lead trailer is higher than the fifth wheel so that the trailer will lower when the dolly is pushed under it

visually check that the rear trailer is lower than the fifth wheel so that the trailer raises slightly when the dolly is pushed under it

you do not need to do a visual check

17 / 40

How should the shut off valves at the rear of the trailer be when inspecting doubles?

open at the rear of the last trailer and front trailer

closed at the rear of the last trailer and open at the rear of the front trailer

closed at the rear of the last trailer and front trailer

none of the answers listed

18 / 40

What is most likely to occur when driving double and a set of trailer wheels goes into a skid?

none of the answers listed

the rig will continue straight ahead but will slide sideways

the trailer will jackknife

the tractor will continue moving in a straight line no matter how you turn the steering wheel

19 / 40

In what position should the shut off valves on a the rear of the front trailer be in on a set of double trailers?

in a 1/3 way open position

in a closed position

in an open position

in a halfway open position

20 / 40

You should keep a minimum of ____between another vehicle and the double trailer with 100 ft truck driving at 30 mph.

13 seconds

10 seconds

15 seconds

8 seconds

21 / 40

How do you release the dolly brakes when coupling twin trailers?

by charging the air line

by flushing the brake line

by opening the air tank petcock

by opening the shut off valve

22 / 40

Remember to____when connecting the converter dolly to the rear trailer.

ensure that the landing gear is slighty off of the ground

all answers listed

lock the trailer brakes

check the trailer height

23 / 40

Select the action that is not recommended when driving on slipper roads:

use a speed retarder or engine brake

use a light pressure with the the brake and accelerator pedals

none of the answers listed

keep other drivers out of your side space

24 / 40

Where are shut off valves located on trailers that are doubles or triples?

on service air lines

on emergency air lines

on parking brake lines

on emergency and service air lines

25 / 40

Select the true statement in regards to driving a truck with triple or double trailers:

extra care should be taken when driving in bad weather and in the mountains

all answers listed

the risk of trailer jackknifes and tipping is increased compared to shorter trucks

the truck requires increased following distance compared to smaller vehicles

26 / 40

The pintle hook should be_____ and the converter dolly air tank drain valve is___when doing a walk around inspection of a triple or double trailer.

latched, open

free, closed

free, open

latched, closed

27 / 40

How should the pintle hook be when backing a dolly under the second trailer?

in a halfway open position

in the unlatched position

in the latched position

removed from the dolly

28 / 40

The crack-the-whip effect is more likely to cause the front trailer to tip over.

there is an equal chance for trailers to tip

true

trailers never tip

false

29 / 40

What is the minimum amount of distance you should maintain when driving at 50 mph in ideal conditions with a 100 ft twin trailer combination?

11 seconds

13 seconds

8 seconds

6 seconds

30 / 40

If you are driving a 100-foot truck with double trailers at 30 mph in dry conditions, how many seconds of space should there be between your truck and other vehicles?

31 / 40

Remember to_____when steering to avoid a crash while driving doubles.

keep your foot off the brake while turning

all answers listed

be prepared to counter-steer

have both hands on the steering wheel

32 / 40

What position should the heaviest trailer be in when pulling 3 trailers?

in the middle

in the back

in the front

it makes no difference

33 / 40

Double and triple trailers should be driven with care to avoid a rollover or jacknife.

only on downgrades

false

true

only in ideal conditions

34 / 40

How do you check the air flow to the last trailer?

watch the brake lights as you step on the brake pedal

pull the vehicle forward and then step on the brakes

while on an level surface, test the emergency brake lines

listen for escaping air after opening the emergency shut off valve

35 / 40

You can be sure air is supplied to the second trailer by:

while driving at 10 mph apply the hand valve you should stop at the same in the same distance as a single trailer driving at 5 mph

watch the air gauge for a drop of 30 psi

going to the rear of the second trailer and open the emergency line shut off

you should get out and listen for air flowing through the lines

36 / 40

When would a drive-wheel skid result in a jackknife when pulling doubles?

when the tractor spins around

when the tractor brakes lock up

when the trailer pushes the towed vehicle sideways

when the trailer slides to the right into the shoulder

37 / 40

Select the statement that is true in regards to managing space to the sides.

high gust winds do not cause any issues for triples and doubles

you should always keep your vehicle to the right side of the lane

you should try to avoid driving next to others when possible

all answers listed

38 / 40

Which trailer should be the first one after the tractor?

the trailer that weighs the most

the trailer that weighs the least

the trailer that is the shortest in length

none of the answers listed

39 / 40

To be sure that air is supplied to the second trailer:

while driving at 10 mph, use the hand valve. The vehicle should stop in the same distance of a single trailer moving at 5 mph

open the emergency line shut off at the back of the second trailer

crank the engine brake

keep an eye of the air gauge for a drop of 30 psi

40 / 40

Select the true statement in regards to unhooking the pintle hook while the converter dolly is still under the trailer.

this is recommended because it keeps the trailer from tipping over

this is recommended as it is standard procedure

this is not recommended because it may result in injury

this is not recommended as it could could cause damage to the pintle hook

Your score is

The average score is 0%

4/5 - (2 votes)

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