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

What is the best way to prevent brakes form overheating while drive down a steep grade?

use the stab braking method

use countersteering practices

use the trailer brakes only

drive at a speed of 5 mph below your safe speed

2 / 40

How do you hook a combination to a second trailer without spring brakes and without using wheel chocks?

make sure th trailer won't roll when coupling

have the trailer electric cord to a generator so it can supply braking power

go ahead and couple it

disconnect the air supply lines after supplying air to the trailer air system via the tractor

3 / 40

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

true

there is an equal chance for trailers to tip

trailers never tip

false

4 / 40

How much space should there be between the lower and upper fifth wheel?

it is dependent on the load you are carrying

zero

1 to 2 inches

1/4 to 1/2 of an inch

5 / 40

Select the true statement in regards to handing triples and doubles

due to off tracking, a triple bottom rig can come to a stop quicker than a 5 axle semi trailer

a sudden movement of the steering wheel may result in the rear trailer tipping over

due to the crack the whip effect, the rear trailer of a 100 foot triple is less likely to tip than a single trailer

none of the answers listed

6 / 40

Remember to_____when steering to avoid a crash while driving doubles.

have both hands on the steering wheel

all answers listed

keep your foot off the brake while turning

be prepared to counter-steer

7 / 40

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

when the trailer pushes the towed vehicle sideways

when the tractor brakes lock up

when the tractor spins around

when the trailer slides to the right into the shoulder

8 / 40

You should check your mirrors while making a lane change:

after you signal your intent to change lanes

right after you start the lane change

all answers listed

after you have completed the lane change

9 / 40

What are the 3 methods for securing a second trailer before coupling?

parking against another trailer, locking the trailer door, and chocking the tires

parking on level ground, chocking the tires, and charging the trailer air tank if it doesn't have spring brakes

all answers listed

chocking the tires, parking on level ground, and charging the air tank

10 / 40

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

there will be a trailer jackknife

the rig will slide sideways but stay in a straight line

nothing will occur

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

11 / 40

You should_____to uncouple the converter dolly.

disconnect the safey chains, lower the landing gear, and chock the wheels

chock the wheels, lower the landing gear, and disconnect the safey chains

chock the wheels, disconnect the safety chains, and then lower the landing gear

lower the landing gear, disconnect the safety chain, and chock the wheels

12 / 40

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

only in ideal conditions

true

only on downgrades

false

13 / 40

For emergency braking when driving a double trailer and having to use your brakes to avoid a collision is to:

use the engine brake

use stab or controlled braking

apply a firm pressure to the brake pedal and don’t let off

use just the trailer brakes

14 / 40

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

in a 1/3 open position

in a closed position

in a halfway closed position

in an open position

15 / 40

Select the true statement about empty trucks:

they have a smaller stopping distance than full trailers

they have poor traction due to wheel lockup and bouncing

empty trailers are easier to stop because there is not cargo shifting

empty trucks stop in the same distance as a fully loaded truck

16 / 40

Select the statement that is true in regards to quick steering movements and triple/double trailers:

as you perform quick steering movements you should apply pressure to the brake pedal

there are no issues that occur from quick steering

it is easier to countersteer compared to other vehicles

they flip over due to quick steering movements a lot easier than other vehicles

17 / 40

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

by opening the air tank petcock

by opening the shut off valve

by charging the air line

by flushing the brake line

18 / 40

How do you secure a second trailer to your combination vehicle?

use the emergency air brakes or the trailer's spring brakes only

use emergency air brakes, spring brakes, and wheel chocks together

use wheel chocks only

none of the answers listed

19 / 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

it is easier to countersteer doubles/triples than other vehicles

nothing will occur

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

20 / 40

Mirrors with a convex surface or "spot" mirrors _____.

are illegal in most states

they show a larger area than flat mirrors so do not need to be checked as often

make things look farther away and smaller than they actually are

make things look closer and larger than they actually are

21 / 40

How do you test the trailer service brakes?

apply the hand control and check to see if you feel the trailer brakes come on

test the brakes out while driving at 5 mph

release air to the spring brakes

apply pressure to the brake pedal

22 / 40

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

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

visually check that they are level height wise

23 / 40

What is the stopping distance for a tractor trailer that is traveling at 55 mph on dry pavement?

about 600 feet with is about two football field lengths

about 150 feet which is 1/2 of a football field

about 300 feet which is about a football field length

about 200 feet which is 2/3 of a football field

24 / 40

Select the true statement about double or triple trailers.

they present a rearward amplification hazard

they can roll over duee to abrupt steering movements

all answers listed

they can have a dangerous "crack the whip" effect

25 / 40

Start by___when coupling.

having the second trailer against the dock

coupling the tractor to the second trailer

coupling the converter hook to the pintle tongue of the first trailer

backing the converter dolly under the second trailer

26 / 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 as it could could cause damage to the pintle hook

this is not recommended because it may result in injury

27 / 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?

13 seconds

11 seconds

6 seconds

8 seconds

28 / 40

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

on emergency and service air lines

on emergency air lines

on service air lines

on parking brake lines

29 / 40

How much space should you see between the lower and upper fifth wheel when checking the coupling of a converter dolly?

1/2 to 1 inch

1 to 1 1/2 inches

none

it depends on how heavy the load is

30 / 40

Which trailer is more likely to roll over when pulling 3 trailers?

the last trailer

the tractor

the second trailer

the first trailer

31 / 40

Select the true statement in regards to converter dollies:

they typically do not have spring brakes

they typically require a hand converter

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

they typically have small braking power because of their size

32 / 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 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

in a open position

in a closed position

33 / 40

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

8 seconds

13 seconds

15 seconds

10 seconds

34 / 40

What is the best way to stop all skids?

quickly turn the steering wheel side to side

use controlled or stab braking

restore traction back to the tires

accelerate and countersteer

35 / 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

the truck requires increased following distance compared to smaller vehicles

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

all answers listed

36 / 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

all answers listed

you should try to avoid driving next to others when possible

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

37 / 40

When driving with multiple trailers, which one should be right behind the tractor?

the trailer with the smallest road

the trailers shortest in length

the trailer longest in length

the trailer with the heaviest load

38 / 40

Which trailer is most likely to tip over due to the crack the whip effect?

the heaviest trailer

the last trailer of a triple

the first trailer of a triples

the last trailer of a double

39 / 40

Remember to____when connecting the converter dolly to the rear trailer.

lock the trailer brakes

all answers listed

check the trailer height

ensure that the landing gear is slighty off of the ground

40 / 40

Why is it dangerous to unlock the pintle hook with the dolly still under the rear trailer?

the spring brakes may release

the fifth wheel may be misaligned

the kingpin may snap in half

the dolly tow bar may fly up

Your score is

The average score is 0%

4/5 - (2 votes)

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