CDL (Commercial Driver)
CDL Air Brakes Practice Test 10
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
Air brake system partsDual air systemsInspecting air brakesUsing air brakes
Preview the first question
What happens when the driver presses the brake pedal in an air brake system?
- The compressor turns off until the truck stops
- Air is released from the brake chambers so that the springs apply
- Brake fluid is pushed through lines to the wheels
- Air is sent to the brake chambers to apply the brakes
Answers are revealed on the results page after you finish.