Free District of Columbia CDL Combination Vehicles Practice Test 2022

You have to pass the CDL combination vehicles endorsement to get ready for propelling your career with your license. You are looking for a good DC CDL practice test source for your coming CDL test? You are in the right place. Our practice test is a great resource for beginners. The CDL practice test is designed for you to have exactly the experience of the exam as you will be more familiar with both the test format and the subject. They cover topics ranging from combination vehicle maintenance to safely driving a complex rig. Each question is based on the official DC CDL Manual so you can be sure that the information in our test is accurate and relevant to your examination. In addition, each question has a detailed explanation so that it is very useful for you to learn from your mistakes. Preparing well before test day with questions and content that we cover. Start with our Free District of Columbia CDL Combination Vehicles Practice Test today and walk out with your endorsement!

Our CDL practice tests:
Based on 2022 DC commercial driver's license manual
Full answers + detailed explanations
Perfect for first-time, renewal applicants
DC CDL Combination Vehicles Test format:
20 questions
16 correct answers to pass
80% passing score
List of questions
1.
Which of the following is part of the electrical and air lines coupling inspection?
2.
Semi-trailers made before 1975 that are equipped with air brakes:
3.
How much space should be allowed between the upper and lower fifth wheel after coupling?
4.
For proper hose coupling, lines are often color-coded. Service lines are usually:
5.
A function of the tractor protection valve is:
6.
Spring brakes are not required on trailers and dollies built before:
7.
Which part of the kingpin should the locking jaw close around?
8.
If the service line comes apart while you are driving a combination vehicle, but the emergency line stays together, what will happen right away?
9.
When pulling trailers:
10.
Which of these statements is true?
11.
What is the term for a commercial vehicle habit of swinging wide on turns?
12.
The emergency air line is usually what color?
13.
You are about to back your tractor under a semitrailer. The trailer is at the right height when the:
14.
After connecting the air lines but before backing under the trailer you should:
15.
To test the tractor protection valve, pump the brakes with the engine off until the trailer air supply knob pops out, usually at:
16.
The hand valve should be used:
17.
Air and electrical lines from the tractor to the trailer should be:
18.
While driving, you should use the trailer hand valve when?
19.
If you cannot complete your turn without entering another traffic lane you should:
20.
A specific item to check on a sliding fifth wheel is: