CDL (Commercial Driver)
CDL Air Brakes Practice Test 7
Free — no payment neededPractice betaLevel: Mixed
20 original CDL Air Brakes questions based on the federal motor carrier safety rules (49 CFR). Practice test, not affiliated with any government agency. Practice beta.
Created by AI
Practice test, not affiliated with any government agency. Original questions written from public sources, checked by a second AI reviewer and automated checks. Rules change; confirm with the official handbook. Available in 2 languages (translations are machine-made and checked automatically).
Before you start
- Questions
- 20 multiple-choice questions, one at a time
- Time
- About 12 minutes. Untimed — take as long as you need.
- Pass mark
- 16 out of 20 correct (80%)
- Feedback
- Your score, the correct answers and short explanations when you finish
- Account
- Not needed. Your answers stay in this browser.
What this test covers
Inspecting air brakesDual air systemsUsing air brakesAir brake system parts
Preview the first question
Before driving a combination vehicle, a driver checks the air lines between the tractor and trailer. What is the goal?
- To lower the build-up time of the compressor before the trip
- To see that air connections are properly made and secured
- To check that the trailer tires match the tractor tires
- To clean dirt from the glad hands only, since the lines are sealed
Answers are revealed on the results page after you finish.