CDL (Commercial Driver)
CDL Air Brakes Practice Test 4
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 partsInspecting air brakesDual air systemsUsing air brakes
Preview the first question
Which newer vehicles must have antilock brakes under federal rules?
- Only buses built after the year 2010 that carry 16 or more people
- Only trailers that carry hazardous materials
- No commercial vehicles; antilock brakes are optional on all of them
- Air-braked truck tractors built on or after March 1, 1997
Answers are revealed on the results page after you finish.