Doubles and Triples Endorsement Test 2024

CDL Doubles and Triples Practice Test

1 / 10

The shut off valves at the rear of the front trailers should be

A) Closed

B) Open

2 / 10

When inspecting the lower fifth wheel, check that locking jaws are around the head of the kingpin, not the shank.

A) False

B) True

3 / 10

You should pull a dolly out from under a trailer after you disconnect it from the trailer in front.

A) True

B) False

4 / 10

How many methods are there to secure a second trailer before coupling?

A) 4

B) 2

C) 3

D) 1

5 / 10

When inspecting the converter dolly, if a spare tire is carried, make sure it is secure. Make sure the pintle-eye of the dolly is in place in the pintle hook of the trailers.

A) True

B) False

6 / 10

What is a coupling device of 1 or 2 axles and a fifth wheel by which a semi- trailer can be coupled to the rear of a tractor-trailer combination forming a double bottom rig?

A) Locking lever

B) Kingpin

C) Trailer line

D) Converter dolly

7 / 10

For safest handling on the road, the more heavily loaded semi-trailer should be in the first position behind the tractor.

A) True

B) False

8 / 10

To check that air flows to all the trailers, you open the emergency line shut-off valve at the rear of the last trailer; you should hear air escaping. Open the service line valve to check that service pressure goes through all the trailers.

A) False

B) True

9 / 10

To check whether or not convert dollies are equipped with ABS, check for a yellow lamp

A) On the left side of the dolly

B) On the right side of the dolly

10 / 10

How do you check to make sure that trailer height is correct before coupling?

A) B and c

B) It must be slightly lower than the center of the fifth wheel, so the trailer is slightly raised when the dolly is pushed under.

C) It must be leveled with the center of the fifth wheel

D) It must be slightly higher than the center of the fifth wheel, so the trailer is slightly lowered when the dolly is pushed over.

Your score is

The average score is 74%

Test Name	CDL Practice Test 2024
Language	English
License	Endorsements Permit
Total Questions	10 sample questions
Test For	Commercial Driver License
Test Preparation	Doubles and Triples Endorsements
Country	USA
Explanation	yes